item_cmpfunc.cc 89 KB
Newer Older
1
/* Copyright (C) 2000-2003 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
unknown's avatar
unknown committed
2

unknown's avatar
unknown committed
3 4 5 6
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
unknown's avatar
unknown committed
7

unknown's avatar
unknown committed
8 9 10 11
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
unknown's avatar
unknown committed
12

unknown's avatar
unknown committed
13 14 15 16 17 18 19
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */


/* This file defines all compare functions */

20
#ifdef USE_PRAGMA_IMPLEMENTATION
unknown's avatar
unknown committed
21 22 23 24 25
#pragma implementation				// gcc: Class implementation
#endif

#include "mysql_priv.h"
#include <m_ctype.h>
26
#include "sql_select.h"
27

28 29
static bool convert_constant_item(THD *thd, Field *field, Item **item);

30 31 32 33 34 35
static Item_result item_store_type(Item_result a,Item_result b)
{
  if (a == STRING_RESULT || b == STRING_RESULT)
    return STRING_RESULT;
  else if (a == REAL_RESULT || b == REAL_RESULT)
    return REAL_RESULT;
unknown's avatar
unknown committed
36 37
  else if (a == DECIMAL_RESULT || b == DECIMAL_RESULT)
    return DECIMAL_RESULT;
38 39 40 41 42 43 44 45 46 47 48 49
  else
    return INT_RESULT;
}

static void agg_result_type(Item_result *type, Item **items, uint nitems)
{
  uint i;
  type[0]= items[0]->result_type();
  for (i=1 ; i < nitems ; i++)
    type[0]= item_store_type(type[0], items[i]->result_type());
}

50 51

static void agg_cmp_type(THD *thd, Item_result *type, Item **items, uint nitems)
52 53
{
  uint i;
54 55 56 57 58 59 60 61 62 63
  Field *field= NULL;
  bool all_constant= TRUE;

  /* If the first argument is a FIELD_ITEM, pull out the field. */
  if (items[0]->type() == Item::FIELD_ITEM)
    field=((Item_field *)items[0])->field;
  /* But if it can't be compared as a longlong, we don't really care. */
  if (field && !field->can_be_compared_as_longlong())
    field= NULL;

64
  type[0]= items[0]->result_type();
65 66
  for (i= 1; i < nitems; i++)
  {
67
    type[0]= item_cmp_type(type[0], items[i]->result_type());
68 69 70 71 72 73 74 75 76 77
    if (field && !convert_constant_item(thd, field, &items[i]))
      all_constant= FALSE;
  }

  /*
    If we had a field that can be compared as a longlong, and all constant
    items, then the aggregate result will be an INT_RESULT.
  */
  if (field && all_constant)
    type[0]= INT_RESULT;
78 79
}

80

unknown's avatar
unknown committed
81 82
static void my_coll_agg_error(DTCollation &c1, DTCollation &c2,
                              const char *fname)
83
{
84 85 86 87
  my_error(ER_CANT_AGGREGATE_2COLLATIONS, MYF(0),
           c1.collation->name,c1.derivation_name(),
           c2.collation->name,c2.derivation_name(),
           fname);
88 89
}

unknown's avatar
unknown committed
90 91

Item_bool_func2* Eq_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
92 93 94
{
  return new Item_func_eq(a, b);
}
unknown's avatar
unknown committed
95 96 97


Item_bool_func2* Ne_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
98 99 100
{
  return new Item_func_ne(a, b);
}
unknown's avatar
unknown committed
101 102 103


Item_bool_func2* Gt_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
104 105 106
{
  return new Item_func_gt(a, b);
}
unknown's avatar
unknown committed
107 108 109


Item_bool_func2* Lt_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
110 111 112
{
  return new Item_func_lt(a, b);
}
unknown's avatar
unknown committed
113 114 115


Item_bool_func2* Ge_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
116 117 118
{
  return new Item_func_ge(a, b);
}
unknown's avatar
unknown committed
119 120 121


Item_bool_func2* Le_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
122 123 124
{
  return new Item_func_le(a, b);
}
unknown's avatar
unknown committed
125

unknown's avatar
unknown committed
126
/*
127
  Test functions
128 129
  Most of these  returns 0LL if false and 1LL if true and
  NULL if some arg is NULL.
unknown's avatar
unknown committed
130 131 132 133
*/

longlong Item_func_not::val_int()
{
134
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
135
  bool value= args[0]->val_bool();
unknown's avatar
unknown committed
136
  null_value=args[0]->null_value;
137
  return ((!null_value && value == 0) ? 1 : 0);
unknown's avatar
unknown committed
138 139
}

140 141 142 143 144
/*
  special NOT for ALL subquery
*/

longlong Item_func_not_all::val_int()
145 146
{
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
147
  bool value= args[0]->val_bool();
148 149

  /*
unknown's avatar
unknown committed
150 151
    return TRUE if there was records in underlying select in max/min
    optimization (ALL subquery)
152 153 154 155
  */
  if (empty_underlying_subquery())
    return 1;

156
  null_value= args[0]->null_value;
157 158 159 160 161 162 163 164
  return ((!null_value && value == 0) ? 1 : 0);
}


bool Item_func_not_all::empty_underlying_subquery()
{
  return ((test_sum_item && !test_sum_item->any_value()) ||
          (test_sub_item && !test_sub_item->any_value()));
165 166
}

unknown's avatar
unknown committed
167 168 169 170 171 172 173 174
void Item_func_not_all::print(String *str)
{
  if (show)
    Item_func::print(str);
  else
    args[0]->print(str);
}

175 176

/*
unknown's avatar
unknown committed
177
  Special NOP (No OPeration) for ALL subquery it is like  Item_func_not_all
unknown's avatar
unknown committed
178
  (return TRUE if underlying subquery do not return rows) but if subquery
unknown's avatar
unknown committed
179
  returns some rows it return same value as argument (TRUE/FALSE).
180 181 182 183 184
*/

longlong Item_func_nop_all::val_int()
{
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
185
  longlong value= args[0]->val_int();
186 187

  /*
unknown's avatar
unknown committed
188 189
    return FALSE if there was records in underlying select in max/min
    optimization (SAME/ANY subquery)
190 191
  */
  if (empty_underlying_subquery())
unknown's avatar
unknown committed
192
    return 0;
193 194 195 196 197 198

  null_value= args[0]->null_value;
  return (null_value || value == 0) ? 0 : 1;
}


unknown's avatar
unknown committed
199 200 201 202 203
/*
  Convert a constant expression or string to an integer.
  This is done when comparing DATE's of different formats and
  also when comparing bigint to strings (in which case the string
  is converted once to a bigint).
unknown's avatar
unknown committed
204 205 206 207

  RESULT VALUES
  0	Can't convert item
  1	Item was replaced with an integer version of the item
unknown's avatar
unknown committed
208
*/
unknown's avatar
unknown committed
209

210
static bool convert_constant_item(THD *thd, Field *field, Item **item)
unknown's avatar
unknown committed
211
{
212
  if ((*item)->const_item())
unknown's avatar
unknown committed
213
  {
214 215 216
    /* For comparison purposes allow invalid dates like 2000-01-32 */
    ulong orig_sql_mode= field->table->in_use->variables.sql_mode;
    field->table->in_use->variables.sql_mode|= MODE_INVALID_DATES;
unknown's avatar
unknown committed
217
    if (!(*item)->save_in_field(field, 1) && !((*item)->null_value))
unknown's avatar
unknown committed
218
    {
unknown's avatar
unknown committed
219 220
      Item *tmp=new Item_int_with_ref(field->val_int(), *item,
                                      test(field->flags & UNSIGNED_FLAG));
221
      field->table->in_use->variables.sql_mode= orig_sql_mode;
222
      if (tmp)
223
        thd->change_item_tree(item, tmp);
224
      return 1;					// Item was replaced
unknown's avatar
unknown committed
225
    }
226
    field->table->in_use->variables.sql_mode= orig_sql_mode;
unknown's avatar
unknown committed
227 228 229 230
  }
  return 0;
}

unknown's avatar
unknown committed
231

232 233 234
void Item_bool_func2::fix_length_and_dec()
{
  max_length= 1;				     // Function returns 0 or 1
235
  THD *thd= current_thd;
236 237 238 239 240 241 242

  /*
    As some compare functions are generated after sql_yacc,
    we have to check for out of memory conditions here
  */
  if (!args[0] || !args[1])
    return;
243 244 245 246 247 248 249 250 251 252 253 254 255

  /* 
    We allow to convert to Unicode character sets in some cases.
    The conditions when conversion is possible are:
    - arguments A and B have different charsets
    - A wins according to coercibility rules
    - character set of A is superset for character set of B
   
    If all of the above is true, then it's possible to convert
    B into the character set of A, and then compare according
    to the collation of A.
  */

256
  
257 258 259
  DTCollation coll;
  if (args[0]->result_type() == STRING_RESULT &&
      args[1]->result_type() == STRING_RESULT &&
unknown's avatar
unknown committed
260 261
      agg_arg_charsets(coll, args, 2, MY_COLL_CMP_CONV))
    return;
262 263
    
 
unknown's avatar
unknown committed
264
  // Make a special case of compare with fields to get nicer DATE comparisons
unknown's avatar
unknown committed
265 266 267 268 269 270

  if (functype() == LIKE_FUNC)  // Disable conversion in case of LIKE function.
  {
    set_cmp_func();
    return;
  }
271 272

  if (!thd->is_context_analysis_only())
unknown's avatar
unknown committed
273
  {
274 275
    Item *real_item= args[0]->real_item();
    if (real_item->type() == FIELD_ITEM)
unknown's avatar
unknown committed
276
    {
277
      Field *field=((Item_field*) real_item)->field;
278
      if (field->can_be_compared_as_longlong())
unknown's avatar
unknown committed
279
      {
280 281 282 283 284 285
        if (convert_constant_item(thd, field,&args[1]))
        {
          cmp.set_cmp_func(this, tmp_arg, tmp_arg+1,
                           INT_RESULT);		// Works for all types.
          return;
        }
unknown's avatar
unknown committed
286 287
      }
    }
288 289
    real_item= args[1]->real_item();
    if (real_item->type() == FIELD_ITEM /* && !real_item->const_item() */)
unknown's avatar
unknown committed
290
    {
291
      Field *field=((Item_field*) real_item)->field;
292
      if (field->can_be_compared_as_longlong())
unknown's avatar
unknown committed
293
      {
294 295 296 297 298 299
        if (convert_constant_item(thd, field,&args[0]))
        {
          cmp.set_cmp_func(this, tmp_arg, tmp_arg+1,
                           INT_RESULT); // Works for all types.
          return;
        }
unknown's avatar
unknown committed
300 301 302
      }
    }
  }
303
  set_cmp_func();
unknown's avatar
unknown committed
304 305
}

306

307
int Arg_comparator::set_compare_func(Item_bool_func2 *item, Item_result type)
unknown's avatar
unknown committed
308
{
309
  owner= item;
unknown's avatar
unknown committed
310 311
  func= comparator_matrix[type]
                         [test(owner->functype() == Item_func::EQUAL_FUNC)];
unknown's avatar
unknown committed
312
  switch (type) {
unknown's avatar
unknown committed
313
  case ROW_RESULT:
unknown's avatar
unknown committed
314
  {
315 316
    uint n= (*a)->cols();
    if (n != (*b)->cols())
317
    {
unknown's avatar
unknown committed
318
      my_error(ER_OPERAND_COLUMNS, MYF(0), n);
319 320 321
      comparators= 0;
      return 1;
    }
322
    if (!(comparators= new Arg_comparator[n]))
unknown's avatar
unknown committed
323 324 325 326
      return 1;
    for (uint i=0; i < n; i++)
    {
      if ((*a)->el(i)->cols() != (*b)->el(i)->cols())
unknown's avatar
unknown committed
327
      {
unknown's avatar
unknown committed
328
	my_error(ER_OPERAND_COLUMNS, MYF(0), (*a)->el(i)->cols());
unknown's avatar
unknown committed
329
	return 1;
unknown's avatar
unknown committed
330
      }
unknown's avatar
unknown committed
331 332
      comparators[i].set_cmp_func(owner, (*a)->addr(i), (*b)->addr(i));
    }
unknown's avatar
unknown committed
333
    break;
334
  }
unknown's avatar
unknown committed
335
  case STRING_RESULT:
336 337 338 339 340
  {
    /*
      We must set cmp_charset here as we may be called from for an automatic
      generated item, like in natural join
    */
341 342
    if (cmp_collation.set((*a)->collation, (*b)->collation) || 
	cmp_collation.derivation == DERIVATION_NONE)
343 344 345 346
    {
      my_coll_agg_error((*a)->collation, (*b)->collation, owner->func_name());
      return 1;
    }
347
    if (cmp_collation.collation == &my_charset_bin)
unknown's avatar
unknown committed
348 349
    {
      /*
350
	We are using BLOB/BINARY/VARBINARY, change to compare byte by byte,
unknown's avatar
unknown committed
351 352 353 354 355 356
	without removing end space
      */
      if (func == &Arg_comparator::compare_string)
	func= &Arg_comparator::compare_binary_string;
      else if (func == &Arg_comparator::compare_e_string)
	func= &Arg_comparator::compare_e_binary_string;
unknown's avatar
unknown committed
357 358

      /*
unknown's avatar
unknown committed
359
        As this is binary compassion, mark all fields that they can't be
unknown's avatar
unknown committed
360 361 362 363 364 365 366 367
        transformed. Otherwise we would get into trouble with comparisons
        like:
        WHERE col= 'j' AND col LIKE BINARY 'j'
        which would be transformed to:
        WHERE col= 'j'
      */
      (*a)->transform(&Item::set_no_const_sub, (byte*) 0);
      (*b)->transform(&Item::set_no_const_sub, (byte*) 0);
unknown's avatar
unknown committed
368
    }
unknown's avatar
unknown committed
369
    break;
370
  }
unknown's avatar
unknown committed
371
  case INT_RESULT:
372
  {
373
    if (func == &Arg_comparator::compare_int_signed)
374 375
    {
      if ((*a)->unsigned_flag)
unknown's avatar
unknown committed
376 377 378
        func= (((*b)->unsigned_flag)?
               &Arg_comparator::compare_int_unsigned :
               &Arg_comparator::compare_int_unsigned_signed);
379 380 381
      else if ((*b)->unsigned_flag)
        func= &Arg_comparator::compare_int_signed_unsigned;
    }
382 383 384 385 386
    else if (func== &Arg_comparator::compare_e_int)
    {
      if ((*a)->unsigned_flag ^ (*b)->unsigned_flag)
        func= &Arg_comparator::compare_e_int_diff_signedness;
    }
unknown's avatar
unknown committed
387 388 389 390 391 392 393
    break;
  }
  case DECIMAL_RESULT:
  case REAL_RESULT:
    break;
  default:
    DBUG_ASSERT(0);
394
  }
395
  return 0;
unknown's avatar
unknown committed
396
}
unknown's avatar
unknown committed
397

unknown's avatar
unknown committed
398

399
int Arg_comparator::compare_string()
unknown's avatar
unknown committed
400 401
{
  String *res1,*res2;
402
  if ((res1= (*a)->val_str(&owner->tmp_value1)))
unknown's avatar
unknown committed
403
  {
404
    if ((res2= (*b)->val_str(&owner->tmp_value2)))
unknown's avatar
unknown committed
405
    {
unknown's avatar
unknown committed
406
      owner->null_value= 0;
407
      return sortcmp(res1,res2,cmp_collation.collation);
unknown's avatar
unknown committed
408 409
    }
  }
unknown's avatar
unknown committed
410
  owner->null_value= 1;
unknown's avatar
unknown committed
411 412 413
  return -1;
}

unknown's avatar
unknown committed
414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446

/*
  Compare strings byte by byte. End spaces are also compared.

  RETURN
   < 0	*a < *b
   0	*b == *b
   > 0	*a > *b
*/

int Arg_comparator::compare_binary_string()
{
  String *res1,*res2;
  if ((res1= (*a)->val_str(&owner->tmp_value1)))
  {
    if ((res2= (*b)->val_str(&owner->tmp_value2)))
    {
      owner->null_value= 0;
      uint res1_length= res1->length();
      uint res2_length= res2->length();
      int cmp= memcmp(res1->ptr(), res2->ptr(), min(res1_length,res2_length));
      return cmp ? cmp : (int) (res1_length - res2_length);
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare strings, but take into account that NULL == NULL
*/

unknown's avatar
unknown committed
447 448 449
int Arg_comparator::compare_e_string()
{
  String *res1,*res2;
450 451
  res1= (*a)->val_str(&owner->tmp_value1);
  res2= (*b)->val_str(&owner->tmp_value2);
unknown's avatar
unknown committed
452 453
  if (!res1 || !res2)
    return test(res1 == res2);
454
  return test(sortcmp(res1, res2, cmp_collation.collation) == 0);
unknown's avatar
unknown committed
455 456 457
}


unknown's avatar
unknown committed
458 459 460 461 462 463 464 465 466 467 468
int Arg_comparator::compare_e_binary_string()
{
  String *res1,*res2;
  res1= (*a)->val_str(&owner->tmp_value1);
  res2= (*b)->val_str(&owner->tmp_value2);
  if (!res1 || !res2)
    return test(res1 == res2);
  return test(stringcmp(res1, res2) == 0);
}


469
int Arg_comparator::compare_real()
unknown's avatar
unknown committed
470
{
471 472 473 474 475 476
  /*
    Fix yet another manifestation of Bug#2338. 'Volatile' will instruct
    gcc to flush double values out of 80-bit Intel FPU registers before
    performing the comparison.
  */
  volatile double val1, val2;
unknown's avatar
Merge  
unknown committed
477
  val1= (*a)->val_real();
478
  if (!(*a)->null_value)
unknown's avatar
unknown committed
479
  {
unknown's avatar
Merge  
unknown committed
480
    val2= (*b)->val_real();
481
    if (!(*b)->null_value)
unknown's avatar
unknown committed
482
    {
unknown's avatar
unknown committed
483
      owner->null_value= 0;
unknown's avatar
unknown committed
484 485 486 487 488
      if (val1 < val2)	return -1;
      if (val1 == val2) return 0;
      return 1;
    }
  }
unknown's avatar
unknown committed
489
  owner->null_value= 1;
unknown's avatar
unknown committed
490 491 492
  return -1;
}

unknown's avatar
unknown committed
493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510
int Arg_comparator::compare_decimal()
{
  my_decimal value1;
  my_decimal *val1= (*a)->val_decimal(&value1);
  if (!(*a)->null_value)
  {
    my_decimal value2;
    my_decimal *val2= (*b)->val_decimal(&value2);
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      return my_decimal_cmp(val1, val2);
    }
  }
  owner->null_value= 1;
  return -1;
}

unknown's avatar
unknown committed
511 512
int Arg_comparator::compare_e_real()
{
513 514
  double val1= (*a)->val_real();
  double val2= (*b)->val_real();
515 516
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
unknown's avatar
unknown committed
517 518
  return test(val1 == val2);
}
unknown's avatar
unknown committed
519

unknown's avatar
unknown committed
520 521 522 523 524 525 526 527 528 529
int Arg_comparator::compare_e_decimal()
{
  my_decimal value1, value2;
  my_decimal *val1= (*a)->val_decimal(&value1);
  my_decimal *val2= (*b)->val_decimal(&value2);
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
  return test(my_decimal_cmp(val1, val2) == 0);
}

530
int Arg_comparator::compare_int_signed()
unknown's avatar
unknown committed
531
{
532 533
  longlong val1= (*a)->val_int();
  if (!(*a)->null_value)
unknown's avatar
unknown committed
534
  {
535 536
    longlong val2= (*b)->val_int();
    if (!(*b)->null_value)
unknown's avatar
unknown committed
537
    {
unknown's avatar
unknown committed
538
      owner->null_value= 0;
unknown's avatar
unknown committed
539 540 541 542 543
      if (val1 < val2)	return -1;
      if (val1 == val2)   return 0;
      return 1;
    }
  }
unknown's avatar
unknown committed
544
  owner->null_value= 1;
unknown's avatar
unknown committed
545 546 547
  return -1;
}

548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623

/*
  Compare values as BIGINT UNSIGNED.
*/

int Arg_comparator::compare_int_unsigned()
{
  ulonglong val1= (*a)->val_int();
  if (!(*a)->null_value)
  {
    ulonglong val2= (*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      if (val1 < val2)	return -1;
      if (val1 == val2)   return 0;
      return 1;
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare signed (*a) with unsigned (*B)
*/

int Arg_comparator::compare_int_signed_unsigned()
{
  longlong sval1= (*a)->val_int();
  if (!(*a)->null_value)
  {
    ulonglong uval2= (ulonglong)(*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      if (sval1 < 0 || (ulonglong)sval1 < uval2)
        return -1;
      if ((ulonglong)sval1 == uval2)
        return 0;
      return 1;
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare unsigned (*a) with signed (*B)
*/

int Arg_comparator::compare_int_unsigned_signed()
{
  ulonglong uval1= (ulonglong)(*a)->val_int();
  if (!(*a)->null_value)
  {
    longlong sval2= (*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      if (sval2 < 0)
        return 1;
      if (uval1 < (ulonglong)sval2)
        return -1;
      if (uval1 == (ulonglong)sval2)
        return 0;
      return 1;
    }
  }
  owner->null_value= 1;
  return -1;
}


unknown's avatar
unknown committed
624 625
int Arg_comparator::compare_e_int()
{
626 627 628 629
  longlong val1= (*a)->val_int();
  longlong val2= (*b)->val_int();
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
unknown's avatar
unknown committed
630 631 632
  return test(val1 == val2);
}

633 634 635 636 637 638 639 640 641 642 643
/*
  Compare unsigned *a with signed *b or signed *a with unsigned *b.
*/
int Arg_comparator::compare_e_int_diff_signedness()
{
  longlong val1= (*a)->val_int();
  longlong val2= (*b)->val_int();
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
  return (val1 >= 0) && test(val1 == val2);
}
unknown's avatar
unknown committed
644

645
int Arg_comparator::compare_row()
unknown's avatar
unknown committed
646 647
{
  int res= 0;
648
  bool was_null= 0;
649 650
  (*a)->bring_value();
  (*b)->bring_value();
651
  uint n= (*a)->cols();
unknown's avatar
unknown committed
652
  for (uint i= 0; i<n; i++)
unknown's avatar
unknown committed
653
  {
654
    res= comparators[i].compare();
unknown's avatar
unknown committed
655
    if (owner->null_value)
656 657 658 659 660 661 662 663
    {
      // NULL was compared
      if (owner->abort_on_null)
        return -1; // We do not need correct NULL returning
      was_null= 1;
      owner->null_value= 0;
      res= 0;  // continue comparison (maybe we will meet explicit difference)
    }
664
    else if (res)
665
      return res;
unknown's avatar
unknown committed
666
  }
667 668 669 670 671 672 673 674 675 676
  if (was_null)
  {
    /*
      There was NULL(s) in comparison in some parts, but there was not
      explicit difference in other parts, so we have to return NULL
    */
    owner->null_value= 1;
    return -1;
  }
  return 0;
unknown's avatar
unknown committed
677
}
unknown's avatar
unknown committed
678

679

unknown's avatar
unknown committed
680 681
int Arg_comparator::compare_e_row()
{
682 683
  (*a)->bring_value();
  (*b)->bring_value();
684
  uint n= (*a)->cols();
unknown's avatar
unknown committed
685 686
  for (uint i= 0; i<n; i++)
  {
unknown's avatar
unknown committed
687
    if (!comparators[i].compare())
688
      return 0;
unknown's avatar
unknown committed
689 690 691 692
  }
  return 1;
}

693

694
bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
unknown's avatar
unknown committed
695
{
696
  if (!args[0]->fixed && args[0]->fix_fields(thd, args) ||
unknown's avatar
unknown committed
697
      !cache && !(cache= Item_cache::get_cache(args[0]->result_type())))
698
    return 1;
699

700
  cache->setup(args[0]);
701 702 703 704
  /*
    If it is preparation PS only then we do not know values of parameters =>
    cant't get there values and do not need that values.
  */
unknown's avatar
unknown committed
705
  if (!thd->stmt_arena->is_stmt_prepare())
706
    cache->store(args[0]);
707
  if (cache->cols() == 1)
708
  {
unknown's avatar
unknown committed
709
    if ((used_tables_cache= args[0]->used_tables()))
unknown's avatar
unknown committed
710
      cache->set_used_tables(OUTER_REF_TABLE_BIT);
711 712 713
    else
      cache->set_used_tables(0);
  }
714 715 716 717
  else
  {
    uint n= cache->cols();
    for (uint i= 0; i < n; i++)
718 719
    {
      if (args[0]->el(i)->used_tables())
unknown's avatar
unknown committed
720
	((Item_cache *)cache->el(i))->set_used_tables(OUTER_REF_TABLE_BIT);
721 722 723
      else
	((Item_cache *)cache->el(i))->set_used_tables(0);
    }
unknown's avatar
unknown committed
724
    used_tables_cache= args[0]->used_tables();
725
  }
unknown's avatar
unknown committed
726 727 728
  not_null_tables_cache= args[0]->not_null_tables();
  with_sum_func= args[0]->with_sum_func;
  const_item_cache= args[0]->const_item();
729 730 731 732
  return 0;
}


733
bool Item_in_optimizer::fix_fields(THD *thd, Item **ref)
734
{
735
  DBUG_ASSERT(fixed == 0);
736
  if (fix_left(thd, ref))
unknown's avatar
unknown committed
737
    return TRUE;
738 739 740
  if (args[0]->maybe_null)
    maybe_null=1;

741
  if (!args[1]->fixed && args[1]->fix_fields(thd, args+1))
unknown's avatar
unknown committed
742
    return TRUE;
unknown's avatar
unknown committed
743 744 745
  Item_in_subselect * sub= (Item_in_subselect *)args[1];
  if (args[0]->cols() != sub->engine->cols())
  {
unknown's avatar
unknown committed
746
    my_error(ER_OPERAND_COLUMNS, MYF(0), args[0]->cols());
unknown's avatar
unknown committed
747
    return TRUE;
unknown's avatar
unknown committed
748
  }
749 750 751 752
  if (args[1]->maybe_null)
    maybe_null=1;
  with_sum_func= with_sum_func || args[1]->with_sum_func;
  used_tables_cache|= args[1]->used_tables();
unknown's avatar
unknown committed
753
  not_null_tables_cache|= args[1]->not_null_tables();
754
  const_item_cache&= args[1]->const_item();
755
  fixed= 1;
unknown's avatar
unknown committed
756
  return FALSE;
757 758
}

759

760 761
longlong Item_in_optimizer::val_int()
{
762
  DBUG_ASSERT(fixed == 1);
763 764
  cache->store(args[0]);
  if (cache->null_value)
765
  {
766
    null_value= 1;
767 768
    return 0;
  }
unknown's avatar
unknown committed
769
  bool tmp= args[1]->val_bool_result();
unknown's avatar
unknown committed
770
  null_value= args[1]->null_value;
771 772 773
  return tmp;
}

774 775 776 777 778 779 780 781

void Item_in_optimizer::keep_top_level_cache()
{
  cache->keep_array();
  save_cache= 1;
}


unknown's avatar
unknown committed
782 783 784 785
void Item_in_optimizer::cleanup()
{
  DBUG_ENTER("Item_in_optimizer::cleanup");
  Item_bool_func::cleanup();
786 787
  if (!save_cache)
    cache= 0;
unknown's avatar
unknown committed
788 789 790
  DBUG_VOID_RETURN;
}

791

792
bool Item_in_optimizer::is_null()
793
{
794 795
  cache->store(args[0]);
  return (null_value= (cache->null_value || args[1]->is_null()));
796
}
unknown's avatar
unknown committed
797

798

unknown's avatar
unknown committed
799 800
longlong Item_func_eq::val_int()
{
801
  DBUG_ASSERT(fixed == 1);
802
  int value= cmp.compare();
unknown's avatar
unknown committed
803 804 805
  return value == 0 ? 1 : 0;
}

806

unknown's avatar
unknown committed
807 808
/* Same as Item_func_eq, but NULL = NULL */

unknown's avatar
unknown committed
809 810 811 812 813 814
void Item_func_equal::fix_length_and_dec()
{
  Item_bool_func2::fix_length_and_dec();
  maybe_null=null_value=0;
}

unknown's avatar
unknown committed
815 816
longlong Item_func_equal::val_int()
{
817
  DBUG_ASSERT(fixed == 1);
818
  return cmp.compare();
unknown's avatar
unknown committed
819 820 821 822
}

longlong Item_func_ne::val_int()
{
823
  DBUG_ASSERT(fixed == 1);
824
  int value= cmp.compare();
825
  return value != 0 && !null_value ? 1 : 0;
unknown's avatar
unknown committed
826 827 828 829 830
}


longlong Item_func_ge::val_int()
{
831
  DBUG_ASSERT(fixed == 1);
832
  int value= cmp.compare();
unknown's avatar
unknown committed
833 834 835 836 837 838
  return value >= 0 ? 1 : 0;
}


longlong Item_func_gt::val_int()
{
839
  DBUG_ASSERT(fixed == 1);
840
  int value= cmp.compare();
unknown's avatar
unknown committed
841 842 843 844 845
  return value > 0 ? 1 : 0;
}

longlong Item_func_le::val_int()
{
846
  DBUG_ASSERT(fixed == 1);
847
  int value= cmp.compare();
unknown's avatar
unknown committed
848 849 850 851 852 853
  return value <= 0 && !null_value ? 1 : 0;
}


longlong Item_func_lt::val_int()
{
854
  DBUG_ASSERT(fixed == 1);
855
  int value= cmp.compare();
unknown's avatar
unknown committed
856 857 858 859 860 861
  return value < 0 && !null_value ? 1 : 0;
}


longlong Item_func_strcmp::val_int()
{
862
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
863 864 865 866 867 868 869
  String *a=args[0]->val_str(&tmp_value1);
  String *b=args[1]->val_str(&tmp_value2);
  if (!a || !b)
  {
    null_value=1;
    return 0;
  }
870
  int value= sortcmp(a,b,cmp.cmp_collation.collation);
unknown's avatar
unknown committed
871 872 873 874 875 876 877
  null_value=0;
  return !value ? 0 : (value < 0 ? (longlong) -1 : (longlong) 1);
}


void Item_func_interval::fix_length_and_dec()
{
unknown's avatar
unknown committed
878 879
  use_decimal_comparison= (row->el(0)->result_type() == DECIMAL_RESULT) ||
    (row->el(0)->result_type() == INT_RESULT);
880
  if (row->cols() > 8)
unknown's avatar
unknown committed
881
  {
882 883 884
    bool consts=1;

    for (uint i=1 ; consts && i < row->cols() ; i++)
unknown's avatar
unknown committed
885
    {
886
      consts&= row->el(i)->const_item();
unknown's avatar
unknown committed
887
    }
888 889

    if (consts &&
unknown's avatar
unknown committed
890 891
        (intervals=
          (interval_range*) sql_alloc(sizeof(interval_range)*(row->cols()-1))))
unknown's avatar
unknown committed
892
    {
unknown's avatar
unknown committed
893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924
      if (use_decimal_comparison)
      {
        for (uint i=1 ; i < row->cols(); i++)
        {
          Item *el= row->el(i);
          interval_range *range= intervals + (i-1);
          if ((el->result_type() == DECIMAL_RESULT) ||
              (el->result_type() == INT_RESULT))
          {
            range->type= DECIMAL_RESULT;
            range->dec.init();
            my_decimal *dec= el->val_decimal(&range->dec);
            if (dec != &range->dec)
            {
              range->dec= *dec;
              range->dec.fix_buffer_pointer();
            }
          }
          else
          {
            range->type= REAL_RESULT;
            range->dbl= el->val_real();
          }
        }
      }
      else
      {
        for (uint i=1 ; i < row->cols(); i++)
        {
          intervals[i-1].dbl= row->el(i)->val_real();
        }
      }
unknown's avatar
unknown committed
925 926
    }
  }
unknown's avatar
unknown committed
927 928
  maybe_null= 0;
  max_length= 2;
929
  used_tables_cache|= row->used_tables();
unknown's avatar
unknown committed
930
  not_null_tables_cache= row->not_null_tables();
931
  with_sum_func= with_sum_func || row->with_sum_func;
unknown's avatar
unknown committed
932
  const_item_cache&= row->const_item();
unknown's avatar
unknown committed
933 934
}

unknown's avatar
unknown committed
935

unknown's avatar
unknown committed
936
/*
unknown's avatar
unknown committed
937 938 939 940 941 942 943 944 945 946 947 948 949 950
  Execute Item_func_interval()

  SYNOPSIS
    Item_func_interval::val_int()

  NOTES
    If we are doing a decimal comparison, we are
    evaluating the first item twice.

  RETURN
    -1 if null value,
    0 if lower than lowest
    1 - arg_count-1 if between args[n] and args[n+1]
    arg_count if higher than biggest argument
unknown's avatar
unknown committed
951 952 953 954
*/

longlong Item_func_interval::val_int()
{
955
  DBUG_ASSERT(fixed == 1);
956
  double value;
unknown's avatar
unknown committed
957
  my_decimal dec_buf, *dec= NULL;
unknown's avatar
unknown committed
958 959
  uint i;

unknown's avatar
unknown committed
960 961 962
  if (use_decimal_comparison)
  {
    dec= row->el(0)->val_decimal(&dec_buf);
963 964 965 966 967 968 969 970 971
    if (row->el(0)->null_value)
      return -1;
    my_decimal2double(E_DEC_FATAL_ERROR, dec, &value);
  }
  else
  {
    value= row->el(0)->val_real();
    if (row->el(0)->null_value)
      return -1;
unknown's avatar
unknown committed
972
  }
unknown's avatar
unknown committed
973

unknown's avatar
unknown committed
974 975 976
  if (intervals)
  {					// Use binary search to find interval
    uint start,end;
977
    start= 0;
unknown's avatar
unknown committed
978
    end=   row->cols()-2;
unknown's avatar
unknown committed
979 980
    while (start != end)
    {
unknown's avatar
unknown committed
981
      uint mid= (start + end + 1) / 2;
unknown's avatar
unknown committed
982 983
      interval_range *range= intervals + mid;
      my_bool cmp_result;
unknown's avatar
unknown committed
984 985 986 987 988
      /*
        The values in the range intervall may have different types,
        Only do a decimal comparision of the first argument is a decimal
        and we are comparing against a decimal
      */
unknown's avatar
unknown committed
989 990 991 992 993
      if (dec && range->type == DECIMAL_RESULT)
        cmp_result= my_decimal_cmp(&range->dec, dec) <= 0;
      else
        cmp_result= (range->dbl <= value);
      if (cmp_result)
unknown's avatar
unknown committed
994
	start= mid;
unknown's avatar
unknown committed
995
      else
unknown's avatar
unknown committed
996
	end= mid - 1;
unknown's avatar
unknown committed
997
    }
unknown's avatar
unknown committed
998 999
    interval_range *range= intervals+start;
    return ((dec && range->type == DECIMAL_RESULT) ?
unknown's avatar
unknown committed
1000
            my_decimal_cmp(dec, &range->dec) < 0 :
unknown's avatar
unknown committed
1001
            value < range->dbl) ? 0 : start + 1;
unknown's avatar
unknown committed
1002
  }
1003 1004

  for (i=1 ; i < row->cols() ; i++)
unknown's avatar
unknown committed
1005
  {
unknown's avatar
unknown committed
1006 1007 1008 1009 1010 1011 1012 1013 1014
    Item *el= row->el(i);
    if (use_decimal_comparison &&
        ((el->result_type() == DECIMAL_RESULT) ||
         (el->result_type() == INT_RESULT)))
    {
      my_decimal e_dec_buf, *e_dec= row->el(i)->val_decimal(&e_dec_buf);
      if (my_decimal_cmp(e_dec, dec) > 0)
        return i-1;
    }
unknown's avatar
unknown committed
1015 1016
    else if (row->el(i)->val_real() > value)
      return i-1;
unknown's avatar
unknown committed
1017
  }
1018
  return i-1;
unknown's avatar
unknown committed
1019 1020
}

unknown's avatar
unknown committed
1021

unknown's avatar
unknown committed
1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050
/*
  Perform context analysis of a BETWEEN item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_between as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(e BETWEEN e1 AND e2)     = union(T1(e),T1(e1),T1(e2))
      T1(e BETWEEN e1 AND e2)     = union(T1(e),intersection(T1(e1),T1(e2)))
      T0(e NOT BETWEEN e1 AND e2) = union(T1(e),intersection(T1(e1),T1(e2)))
      T1(e NOT BETWEEN e1 AND e2) = union(T1(e),intersection(T1(e1),T1(e2)))

  RETURN
    0   ok
    1   got error
*/

unknown's avatar
unknown committed
1051
bool Item_func_between::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
1052
{
1053
  if (Item_func_opt_neg::fix_fields(thd, ref))
unknown's avatar
unknown committed
1054 1055 1056 1057 1058 1059 1060
    return 1;

  /* not_null_tables_cache == union(T1(e),T1(e1),T1(e2)) */
  if (pred_level && !negated)
    return 0;

  /* not_null_tables_cache == union(T1(e), intersection(T1(e1),T1(e2))) */
unknown's avatar
unknown committed
1061 1062 1063
  not_null_tables_cache= (args[0]->not_null_tables() |
                          (args[1]->not_null_tables() &
                           args[2]->not_null_tables()));
unknown's avatar
unknown committed
1064 1065 1066 1067 1068

  return 0;
}


unknown's avatar
unknown committed
1069 1070
void Item_func_between::fix_length_and_dec()
{
unknown's avatar
unknown committed
1071
   max_length= 1;
1072
   THD *thd= current_thd;
unknown's avatar
unknown committed
1073

1074 1075
  /*
    As some compare functions are generated after sql_yacc,
unknown's avatar
unknown committed
1076
    we have to check for out of memory conditions here
1077
  */
unknown's avatar
unknown committed
1078 1079
  if (!args[0] || !args[1] || !args[2])
    return;
1080 1081
  agg_cmp_type(thd, &cmp_type, args, 3);

unknown's avatar
unknown committed
1082
  if (cmp_type == STRING_RESULT &&
unknown's avatar
unknown committed
1083
      agg_arg_charsets(cmp_collation, args, 3, MY_COLL_CMP_CONV))
unknown's avatar
unknown committed
1084
    return;
unknown's avatar
unknown committed
1085 1086 1087 1088 1089
}


longlong Item_func_between::val_int()
{						// ANSI BETWEEN
1090
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1091 1092 1093 1094 1095 1096 1097 1098 1099
  if (cmp_type == STRING_RESULT)
  {
    String *value,*a,*b;
    value=args[0]->val_str(&value0);
    if ((null_value=args[0]->null_value))
      return 0;
    a=args[1]->val_str(&value1);
    b=args[2]->val_str(&value2);
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
1100 1101 1102
      return (longlong) ((sortcmp(value,a,cmp_collation.collation) >= 0 &&
                          sortcmp(value,b,cmp_collation.collation) <= 0) !=
                         negated);
unknown's avatar
unknown committed
1103 1104 1105 1106
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
unknown's avatar
unknown committed
1107 1108
      // Set to not null if false range.
      null_value= sortcmp(value,b,cmp_collation.collation) <= 0;
unknown's avatar
unknown committed
1109 1110 1111
    }
    else
    {
unknown's avatar
unknown committed
1112 1113
      // Set to not null if false range.
      null_value= sortcmp(value,a,cmp_collation.collation) >= 0;
unknown's avatar
unknown committed
1114 1115 1116 1117
    }
  }
  else if (cmp_type == INT_RESULT)
  {
1118
    longlong value=args[0]->val_int(), a, b;
unknown's avatar
unknown committed
1119
    if ((null_value=args[0]->null_value))
1120
      return 0;					/* purecov: inspected */
unknown's avatar
unknown committed
1121 1122 1123
    a=args[1]->val_int();
    b=args[2]->val_int();
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
1124
      return (longlong) ((value >= a && value <= b) != negated);
unknown's avatar
unknown committed
1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
      null_value= value <= b;			// not null if false range.
    }
    else
    {
      null_value= value >= a;
    }
  }
unknown's avatar
unknown committed
1136 1137 1138 1139 1140 1141 1142 1143 1144
  else if (cmp_type == DECIMAL_RESULT)
  {
    my_decimal dec_buf, *dec= args[0]->val_decimal(&dec_buf),
               a_buf, *a_dec, b_buf, *b_dec;
    if ((null_value=args[0]->null_value))
      return 0;					/* purecov: inspected */
    a_dec= args[1]->val_decimal(&a_buf);
    b_dec= args[2]->val_decimal(&b_buf);
    if (!args[1]->null_value && !args[2]->null_value)
1145 1146
      return (longlong) ((my_decimal_cmp(dec, a_dec) >= 0 &&
                          my_decimal_cmp(dec, b_dec) <= 0) != negated);
unknown's avatar
unknown committed
1147 1148 1149 1150 1151 1152 1153
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
      null_value= (my_decimal_cmp(dec, b_dec) <= 0);
    else
      null_value= (my_decimal_cmp(dec, a_dec) >= 0);
  }
unknown's avatar
unknown committed
1154 1155
  else
  {
1156
    double value= args[0]->val_real(),a,b;
unknown's avatar
unknown committed
1157
    if ((null_value=args[0]->null_value))
1158
      return 0;					/* purecov: inspected */
1159 1160
    a= args[1]->val_real();
    b= args[2]->val_real();
unknown's avatar
unknown committed
1161
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
1162
      return (longlong) ((value >= a && value <= b) != negated);
unknown's avatar
unknown committed
1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
      null_value= value <= b;			// not null if false range.
    }
    else
    {
      null_value= value >= a;
    }
  }
unknown's avatar
unknown committed
1174
  return (longlong) (!null_value && negated);
unknown's avatar
unknown committed
1175 1176
}

1177 1178 1179 1180 1181

void Item_func_between::print(String *str)
{
  str->append('(');
  args[0]->print(str);
unknown's avatar
unknown committed
1182
  if (negated)
1183 1184
    str->append(STRING_WITH_LEN(" not"));
  str->append(STRING_WITH_LEN(" between "));
1185
  args[1]->print(str);
1186
  str->append(STRING_WITH_LEN(" and "));
1187 1188 1189 1190
  args[2]->print(str);
  str->append(')');
}

unknown's avatar
unknown committed
1191 1192 1193
void
Item_func_ifnull::fix_length_and_dec()
{
1194
  agg_result_type(&hybrid_type, args, 2);
unknown's avatar
unknown committed
1195
  maybe_null=args[1]->maybe_null;
unknown's avatar
unknown committed
1196
  decimals= max(args[0]->decimals, args[1]->decimals);
1197 1198 1199 1200 1201
  max_length= (hybrid_type == DECIMAL_RESULT || hybrid_type == INT_RESULT) ?
    (max(args[0]->max_length - args[0]->decimals,
         args[1]->max_length - args[1]->decimals) + decimals) :
    max(args[0]->max_length, args[1]->max_length);

unknown's avatar
unknown committed
1202
  switch (hybrid_type) {
unknown's avatar
unknown committed
1203
  case STRING_RESULT:
unknown's avatar
unknown committed
1204
    agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV);
unknown's avatar
unknown committed
1205 1206 1207 1208 1209
    break;
  case DECIMAL_RESULT:
  case REAL_RESULT:
    break;
  case INT_RESULT:
1210
    decimals= 0;
unknown's avatar
unknown committed
1211 1212 1213 1214 1215
    break;
  case ROW_RESULT:
  default:
    DBUG_ASSERT(0);
  }
1216 1217 1218
  cached_field_type= args[0]->field_type();
  if (cached_field_type != args[1]->field_type())
    cached_field_type= Item_func::field_type();
unknown's avatar
unknown committed
1219 1220
}

unknown's avatar
unknown committed
1221 1222 1223 1224 1225 1226 1227 1228

uint Item_func_ifnull::decimal_precision() const
{
  int max_int_part=max(args[0]->decimal_int_part(),args[1]->decimal_int_part());
  return min(max_int_part + decimals, DECIMAL_MAX_PRECISION);
}


1229 1230 1231
enum_field_types Item_func_ifnull::field_type() const 
{
  return cached_field_type;
unknown's avatar
unknown committed
1232 1233
}

1234 1235
Field *Item_func_ifnull::tmp_table_field(TABLE *table)
{
unknown's avatar
unknown committed
1236
  return tmp_table_field_from_field_type(table, 0);
1237
}
1238

unknown's avatar
unknown committed
1239
double
unknown's avatar
unknown committed
1240
Item_func_ifnull::real_op()
unknown's avatar
unknown committed
1241
{
1242
  DBUG_ASSERT(fixed == 1);
1243
  double value= args[0]->val_real();
unknown's avatar
unknown committed
1244 1245 1246 1247 1248
  if (!args[0]->null_value)
  {
    null_value=0;
    return value;
  }
1249
  value= args[1]->val_real();
unknown's avatar
unknown committed
1250 1251 1252 1253 1254 1255
  if ((null_value=args[1]->null_value))
    return 0.0;
  return value;
}

longlong
unknown's avatar
unknown committed
1256
Item_func_ifnull::int_op()
unknown's avatar
unknown committed
1257
{
1258
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270
  longlong value=args[0]->val_int();
  if (!args[0]->null_value)
  {
    null_value=0;
    return value;
  }
  value=args[1]->val_int();
  if ((null_value=args[1]->null_value))
    return 0;
  return value;
}

unknown's avatar
unknown committed
1271

unknown's avatar
unknown committed
1272
my_decimal *Item_func_ifnull::decimal_op(my_decimal *decimal_value)
unknown's avatar
unknown committed
1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287
{
  DBUG_ASSERT(fixed == 1);
  my_decimal *value= args[0]->val_decimal(decimal_value);
  if (!args[0]->null_value)
  {
    null_value= 0;
    return value;
  }
  value= args[1]->val_decimal(decimal_value);
  if ((null_value= args[1]->null_value))
    return 0;
  return value;
}


unknown's avatar
unknown committed
1288
String *
unknown's avatar
unknown committed
1289
Item_func_ifnull::str_op(String *str)
unknown's avatar
unknown committed
1290
{
1291
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1292 1293 1294 1295
  String *res  =args[0]->val_str(str);
  if (!args[0]->null_value)
  {
    null_value=0;
1296
    res->set_charset(collation.collation);
unknown's avatar
unknown committed
1297 1298 1299 1300 1301
    return res;
  }
  res=args[1]->val_str(str);
  if ((null_value=args[1]->null_value))
    return 0;
1302
  res->set_charset(collation.collation);
unknown's avatar
unknown committed
1303 1304 1305
  return res;
}

1306

unknown's avatar
unknown committed
1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334
/*
  Perform context analysis of an IF item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_if as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(IF(e,e1,e2)  = T1(IF(e,e1,e2))
      T1(IF(e,e1,e2)) = intersection(T1(e1),T1(e2))

  RETURN
    0   ok
    1   got error
*/

bool
1335
Item_func_if::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
1336 1337 1338 1339
{
  DBUG_ASSERT(fixed == 0);
  args[0]->top_level_item();

1340
  if (Item_func::fix_fields(thd, ref))
unknown's avatar
unknown committed
1341 1342
    return 1;

unknown's avatar
unknown committed
1343 1344
  not_null_tables_cache= (args[1]->not_null_tables() &
                          args[2]->not_null_tables());
unknown's avatar
unknown committed
1345 1346 1347 1348 1349

  return 0;
}


unknown's avatar
unknown committed
1350 1351 1352 1353
void
Item_func_if::fix_length_and_dec()
{
  maybe_null=args[1]->maybe_null || args[2]->maybe_null;
unknown's avatar
unknown committed
1354
  decimals= max(args[1]->decimals, args[2]->decimals);
1355

unknown's avatar
unknown committed
1356 1357
  enum Item_result arg1_type=args[1]->result_type();
  enum Item_result arg2_type=args[2]->result_type();
unknown's avatar
unknown committed
1358 1359
  bool null1=args[1]->const_item() && args[1]->null_value;
  bool null2=args[2]->const_item() && args[2]->null_value;
1360 1361 1362 1363

  if (null1)
  {
    cached_result_type= arg2_type;
1364
    collation.set(args[2]->collation.collation);
1365 1366 1367
  }
  else if (null2)
  {
unknown's avatar
unknown committed
1368
    cached_result_type= arg1_type;
1369
    collation.set(args[1]->collation.collation);
1370
  }
unknown's avatar
unknown committed
1371
  else
1372
  {
1373 1374 1375
    agg_result_type(&cached_result_type, args+1, 2);
    if (cached_result_type == STRING_RESULT)
    {
unknown's avatar
unknown committed
1376
      if (agg_arg_charsets(collation, args+1, 2, MY_COLL_ALLOW_CONV))
1377
        return;
1378
    }
1379
    else
1380
    {
1381
      collation.set(&my_charset_bin);	// Number
1382
    }
1383
  }
1384 1385 1386
  max_length=
    (cached_result_type == DECIMAL_RESULT || cached_result_type == INT_RESULT) ?
    (max(args[1]->max_length - args[1]->decimals,
1387 1388
         args[2]->max_length - args[2]->decimals) + decimals +
         (unsigned_flag ? 0 : 1) ) :
1389
    max(args[1]->max_length, args[2]->max_length);
unknown's avatar
unknown committed
1390 1391 1392
}


unknown's avatar
unknown committed
1393 1394 1395 1396 1397 1398 1399 1400
uint Item_func_if::decimal_precision() const
{
  int precision=(max(args[1]->decimal_int_part(),args[2]->decimal_int_part())+
                 decimals);
  return min(precision, DECIMAL_MAX_PRECISION);
}


unknown's avatar
unknown committed
1401
double
1402
Item_func_if::val_real()
unknown's avatar
unknown committed
1403
{
1404
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1405
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
1406
  double value= arg->val_real();
unknown's avatar
unknown committed
1407 1408 1409 1410 1411 1412 1413
  null_value=arg->null_value;
  return value;
}

longlong
Item_func_if::val_int()
{
1414
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1415
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
unknown's avatar
unknown committed
1416 1417 1418 1419 1420 1421 1422 1423
  longlong value=arg->val_int();
  null_value=arg->null_value;
  return value;
}

String *
Item_func_if::val_str(String *str)
{
1424
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1425
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
unknown's avatar
unknown committed
1426
  String *res=arg->val_str(str);
1427
  if (res)
1428
    res->set_charset(collation.collation);
unknown's avatar
unknown committed
1429 1430 1431 1432 1433
  null_value=arg->null_value;
  return res;
}


unknown's avatar
unknown committed
1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444
my_decimal *
Item_func_if::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
  my_decimal *value= arg->val_decimal(decimal_value);
  null_value= arg->null_value;
  return value;
}


unknown's avatar
unknown committed
1445 1446 1447 1448 1449 1450 1451 1452 1453
void
Item_func_nullif::fix_length_and_dec()
{
  Item_bool_func2::fix_length_and_dec();
  maybe_null=1;
  if (args[0])					// Only false if EOM
  {
    max_length=args[0]->max_length;
    decimals=args[0]->decimals;
unknown's avatar
unknown committed
1454 1455
    unsigned_flag= args[0]->unsigned_flag;
    cached_result_type= args[0]->result_type();
1456 1457 1458
    if (cached_result_type == STRING_RESULT &&
        agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV))
      return;
unknown's avatar
unknown committed
1459 1460 1461
  }
}

unknown's avatar
unknown committed
1462

unknown's avatar
unknown committed
1463
/*
1464
  nullif () returns NULL if arguments are equal, else it returns the
unknown's avatar
unknown committed
1465 1466 1467 1468 1469 1470
  first argument.
  Note that we have to evaluate the first argument twice as the compare
  may have been done with a different type than return value
*/

double
1471
Item_func_nullif::val_real()
unknown's avatar
unknown committed
1472
{
1473
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1474
  double value;
unknown's avatar
unknown committed
1475
  if (!cmp.compare())
unknown's avatar
unknown committed
1476 1477 1478 1479
  {
    null_value=1;
    return 0.0;
  }
1480
  value= args[0]->val_real();
unknown's avatar
unknown committed
1481 1482 1483 1484 1485 1486 1487
  null_value=args[0]->null_value;
  return value;
}

longlong
Item_func_nullif::val_int()
{
1488
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1489
  longlong value;
unknown's avatar
unknown committed
1490
  if (!cmp.compare())
unknown's avatar
unknown committed
1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502
  {
    null_value=1;
    return 0;
  }
  value=args[0]->val_int();
  null_value=args[0]->null_value;
  return value;
}

String *
Item_func_nullif::val_str(String *str)
{
1503
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1504
  String *res;
unknown's avatar
unknown committed
1505
  if (!cmp.compare())
unknown's avatar
unknown committed
1506 1507 1508 1509 1510 1511 1512 1513 1514
  {
    null_value=1;
    return 0;
  }
  res=args[0]->val_str(str);
  null_value=args[0]->null_value;
  return res;
}

1515

unknown's avatar
unknown committed
1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531
my_decimal *
Item_func_nullif::val_decimal(my_decimal * decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  my_decimal *res;
  if (!cmp.compare())
  {
    null_value=1;
    return 0;
  }
  res= args[0]->val_decimal(decimal_value);
  null_value= args[0]->null_value;
  return res;
}


1532 1533 1534
bool
Item_func_nullif::is_null()
{
unknown's avatar
unknown committed
1535
  return (null_value= (!cmp.compare() ? 1 : args[0]->null_value)); 
1536 1537
}

unknown's avatar
unknown committed
1538
/*
1539 1540
  CASE expression 
  Return the matching ITEM or NULL if all compares (including else) failed
unknown's avatar
unknown committed
1541 1542 1543 1544
*/

Item *Item_func_case::find_item(String *str)
{
unknown's avatar
unknown committed
1545 1546
  String *first_expr_str, *tmp;
  my_decimal *first_expr_dec, first_expr_dec_val;
unknown's avatar
unknown committed
1547 1548
  longlong first_expr_int;
  double   first_expr_real;
1549 1550
  char buff[MAX_FIELD_WIDTH];
  String buff_str(buff,sizeof(buff),default_charset());
unknown's avatar
unknown committed
1551

unknown's avatar
unknown committed
1552 1553 1554 1555
  /* These will be initialized later */
  LINT_INIT(first_expr_str);
  LINT_INIT(first_expr_int);
  LINT_INIT(first_expr_real);
unknown's avatar
unknown committed
1556
  LINT_INIT(first_expr_dec);
unknown's avatar
unknown committed
1557

unknown's avatar
unknown committed
1558 1559 1560 1561 1562 1563
  if (first_expr_num != -1)
  {
    switch (cmp_type)
    {
      case STRING_RESULT:
      	// We can't use 'str' here as this may be overwritten
1564
	if (!(first_expr_str= args[first_expr_num]->val_str(&buff_str)))
unknown's avatar
unknown committed
1565 1566 1567 1568 1569 1570 1571 1572
	  return else_expr_num != -1 ? args[else_expr_num] : 0;	// Impossible
        break;
      case INT_RESULT:
	first_expr_int= args[first_expr_num]->val_int();
	if (args[first_expr_num]->null_value)
	  return else_expr_num != -1 ? args[else_expr_num] : 0;
	break;
      case REAL_RESULT:
1573
	first_expr_real= args[first_expr_num]->val_real();
unknown's avatar
unknown committed
1574 1575 1576
	if (args[first_expr_num]->null_value)
	  return else_expr_num != -1 ? args[else_expr_num] : 0;
	break;
unknown's avatar
unknown committed
1577 1578 1579 1580 1581
      case DECIMAL_RESULT:
        first_expr_dec= args[first_expr_num]->val_decimal(&first_expr_dec_val);
        if (args[first_expr_num]->null_value)
          return else_expr_num != -1 ? args[else_expr_num] : 0;
        break;
unknown's avatar
unknown committed
1582 1583
      case ROW_RESULT:
      default:
unknown's avatar
unknown committed
1584
        // This case should never be chosen
unknown's avatar
unknown committed
1585 1586 1587 1588 1589
	DBUG_ASSERT(0);
	break;
    }
  }

unknown's avatar
unknown committed
1590
  // Compare every WHEN argument with it and return the first match
1591
  for (uint i=0 ; i < ncases ; i+=2)
unknown's avatar
unknown committed
1592
  {
1593
    if (first_expr_num == -1)
unknown's avatar
unknown committed
1594
    {
unknown's avatar
unknown committed
1595
      // No expression between CASE and the first WHEN
unknown's avatar
unknown committed
1596
      if (args[i]->val_bool())
unknown's avatar
unknown committed
1597 1598 1599
	return args[i+1];
      continue;
    }
unknown's avatar
unknown committed
1600
    switch (cmp_type) {
unknown's avatar
unknown committed
1601 1602
    case STRING_RESULT:
      if ((tmp=args[i]->val_str(str)))		// If not null
unknown's avatar
unknown committed
1603
	if (sortcmp(tmp,first_expr_str,cmp_collation.collation)==0)
unknown's avatar
unknown committed
1604 1605 1606 1607 1608 1609 1610
	  return args[i+1];
      break;
    case INT_RESULT:
      if (args[i]->val_int()==first_expr_int && !args[i]->null_value) 
        return args[i+1];
      break;
    case REAL_RESULT: 
1611
      if (args[i]->val_real() == first_expr_real && !args[i]->null_value)
unknown's avatar
unknown committed
1612
        return args[i+1];
unknown's avatar
unknown committed
1613
      break;
unknown's avatar
unknown committed
1614 1615 1616 1617 1618 1619 1620
    case DECIMAL_RESULT:
    {
      my_decimal value;
      if (my_decimal_cmp(args[i]->val_decimal(&value), first_expr_dec) == 0)
        return args[i+1];
      break;
    }
1621
    case ROW_RESULT:
unknown's avatar
unknown committed
1622
    default:
unknown's avatar
unknown committed
1623
      // This case should never be chosen
unknown's avatar
unknown committed
1624 1625
      DBUG_ASSERT(0);
      break;
unknown's avatar
unknown committed
1626 1627 1628
    }
  }
  // No, WHEN clauses all missed, return ELSE expression
1629
  return else_expr_num != -1 ? args[else_expr_num] : 0;
unknown's avatar
unknown committed
1630 1631 1632 1633 1634
}


String *Item_func_case::val_str(String *str)
{
1635
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1636 1637 1638 1639 1640 1641 1642 1643
  String *res;
  Item *item=find_item(str);

  if (!item)
  {
    null_value=1;
    return 0;
  }
unknown's avatar
unknown committed
1644
  null_value= 0;
unknown's avatar
unknown committed
1645
  if (!(res=item->val_str(str)))
unknown's avatar
unknown committed
1646
    null_value= 1;
unknown's avatar
unknown committed
1647 1648 1649 1650 1651 1652
  return res;
}


longlong Item_func_case::val_int()
{
1653
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1654
  char buff[MAX_FIELD_WIDTH];
1655
  String dummy_str(buff,sizeof(buff),default_charset());
unknown's avatar
unknown committed
1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668
  Item *item=find_item(&dummy_str);
  longlong res;

  if (!item)
  {
    null_value=1;
    return 0;
  }
  res=item->val_int();
  null_value=item->null_value;
  return res;
}

1669
double Item_func_case::val_real()
unknown's avatar
unknown committed
1670
{
1671
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1672
  char buff[MAX_FIELD_WIDTH];
1673
  String dummy_str(buff,sizeof(buff),default_charset());
unknown's avatar
unknown committed
1674 1675 1676 1677 1678 1679 1680 1681
  Item *item=find_item(&dummy_str);
  double res;

  if (!item)
  {
    null_value=1;
    return 0;
  }
1682
  res= item->val_real();
unknown's avatar
unknown committed
1683 1684 1685 1686
  null_value=item->null_value;
  return res;
}

unknown's avatar
unknown committed
1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707

my_decimal *Item_func_case::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  char buff[MAX_FIELD_WIDTH];
  String dummy_str(buff, sizeof(buff), default_charset());
  Item *item= find_item(&dummy_str);
  my_decimal *res;

  if (!item)
  {
    null_value=1;
    return 0;
  }

  res= item->val_decimal(decimal_value);
  null_value= item->null_value;
  return res;
}


unknown's avatar
unknown committed
1708
bool Item_func_case::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
1709 1710 1711 1712 1713 1714
{
  /*
    buff should match stack usage from
    Item_func_case::val_int() -> Item_func_case::find_item()
  */
  char buff[MAX_FIELD_WIDTH*2+sizeof(String)*2+sizeof(String*)*2+sizeof(double)*2+sizeof(longlong)*2];
unknown's avatar
unknown committed
1715 1716 1717 1718 1719
  bool res= Item_func::fix_fields(thd, ref);
  /*
    Call check_stack_overrun after fix_fields to be sure that stack variable
    is not optimized away
  */
unknown's avatar
unknown committed
1720 1721
  if (check_stack_overrun(thd, STACK_MIN_SIZE, buff))
    return TRUE;				// Fatal error flag is set!
unknown's avatar
unknown committed
1722
  return res;
unknown's avatar
unknown committed
1723 1724 1725 1726
}



unknown's avatar
unknown committed
1727
void Item_func_case::fix_length_and_dec()
1728
{
1729 1730
  Item **agg;
  uint nagg;
1731
  THD *thd= current_thd;
1732 1733 1734 1735
  
  if (!(agg= (Item**) sql_alloc(sizeof(Item*)*(ncases+1))))
    return;
  
1736 1737 1738 1739
  /*
    Aggregate all THEN and ELSE expression types
    and collations when string result
  */
1740 1741 1742 1743 1744 1745 1746 1747 1748
  
  for (nagg= 0 ; nagg < ncases/2 ; nagg++)
    agg[nagg]= args[nagg*2+1];
  
  if (else_expr_num != -1)
    agg[nagg++]= args[else_expr_num];
  
  agg_result_type(&cached_result_type, agg, nagg);
  if ((cached_result_type == STRING_RESULT) &&
unknown's avatar
unknown committed
1749
      agg_arg_charsets(collation, agg, nagg, MY_COLL_ALLOW_CONV))
1750 1751 1752
    return;
  
  
unknown's avatar
unknown committed
1753 1754 1755 1756
  /*
    Aggregate first expression and all THEN expression types
    and collations when string comparison
  */
1757
  if (first_expr_num != -1)
1758
  {
1759 1760
    agg[0]= args[first_expr_num];
    for (nagg= 0; nagg < ncases/2 ; nagg++)
unknown's avatar
unknown committed
1761
      agg[nagg+1]= args[nagg*2];
1762
    nagg++;
1763
    agg_cmp_type(thd, &cmp_type, agg, nagg);
1764
    if ((cmp_type == STRING_RESULT) &&
unknown's avatar
unknown committed
1765
        agg_arg_charsets(cmp_collation, agg, nagg, MY_COLL_CMP_CONV))
unknown's avatar
unknown committed
1766
      return;
1767
  }
1768
  
unknown's avatar
unknown committed
1769
  if (else_expr_num == -1 || args[else_expr_num]->maybe_null)
1770
    maybe_null=1;
1771
  
unknown's avatar
unknown committed
1772 1773
  max_length=0;
  decimals=0;
1774
  for (uint i=0 ; i < ncases ; i+=2)
unknown's avatar
unknown committed
1775 1776 1777 1778
  {
    set_if_bigger(max_length,args[i+1]->max_length);
    set_if_bigger(decimals,args[i+1]->decimals);
  }
1779
  if (else_expr_num != -1) 
unknown's avatar
unknown committed
1780
  {
1781 1782
    set_if_bigger(max_length,args[else_expr_num]->max_length);
    set_if_bigger(decimals,args[else_expr_num]->decimals);
unknown's avatar
unknown committed
1783 1784 1785
  }
}

unknown's avatar
unknown committed
1786

unknown's avatar
unknown committed
1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798
uint Item_func_case::decimal_precision() const
{
  int max_int_part=0;
  for (uint i=0 ; i < ncases ; i+=2)
    set_if_bigger(max_int_part, args[i+1]->decimal_int_part());

  if (else_expr_num != -1) 
    set_if_bigger(max_int_part, args[else_expr_num]->decimal_int_part());
  return min(max_int_part + decimals, DECIMAL_MAX_PRECISION);
}


1799
/* TODO:  Fix this so that it prints the whole CASE expression */
unknown's avatar
unknown committed
1800 1801 1802

void Item_func_case::print(String *str)
{
1803
  str->append(STRING_WITH_LEN("(case "));
1804 1805 1806 1807 1808 1809 1810
  if (first_expr_num != -1)
  {
    args[first_expr_num]->print(str);
    str->append(' ');
  }
  for (uint i=0 ; i < ncases ; i+=2)
  {
1811
    str->append(STRING_WITH_LEN("when "));
1812
    args[i]->print(str);
1813
    str->append(STRING_WITH_LEN(" then "));
1814 1815 1816 1817 1818
    args[i+1]->print(str);
    str->append(' ');
  }
  if (else_expr_num != -1)
  {
1819
    str->append(STRING_WITH_LEN("else "));
1820 1821 1822
    args[else_expr_num]->print(str);
    str->append(' ');
  }
1823
  str->append(STRING_WITH_LEN("end)"));
unknown's avatar
unknown committed
1824 1825 1826
}

/*
1827
  Coalesce - return first not NULL argument.
unknown's avatar
unknown committed
1828 1829
*/

unknown's avatar
unknown committed
1830
String *Item_func_coalesce::str_op(String *str)
unknown's avatar
unknown committed
1831
{
1832
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1833 1834 1835
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
unknown's avatar
unknown committed
1836 1837 1838
    String *res;
    if ((res=args[i]->val_str(str)))
      return res;
unknown's avatar
unknown committed
1839 1840 1841 1842 1843
  }
  null_value=1;
  return 0;
}

unknown's avatar
unknown committed
1844
longlong Item_func_coalesce::int_op()
unknown's avatar
unknown committed
1845
{
1846
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
    longlong res=args[i]->val_int();
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}

unknown's avatar
unknown committed
1858
double Item_func_coalesce::real_op()
unknown's avatar
unknown committed
1859
{
1860
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1861 1862 1863
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
1864
    double res= args[i]->val_real();
unknown's avatar
unknown committed
1865 1866 1867 1868 1869 1870 1871 1872
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}


unknown's avatar
unknown committed
1873
my_decimal *Item_func_coalesce::decimal_op(my_decimal *decimal_value)
unknown's avatar
unknown committed
1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887
{
  DBUG_ASSERT(fixed == 1);
  null_value= 0;
  for (uint i= 0; i < arg_count; i++)
  {
    my_decimal *res= args[i]->val_decimal(decimal_value);
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}


unknown's avatar
unknown committed
1888 1889
void Item_func_coalesce::fix_length_and_dec()
{
unknown's avatar
unknown committed
1890 1891
  agg_result_type(&hybrid_type, args, arg_count);
  switch (hybrid_type) {
unknown's avatar
unknown committed
1892 1893 1894
  case STRING_RESULT:
    count_only_length();
    decimals= NOT_FIXED_DEC;
unknown's avatar
unknown committed
1895
    agg_arg_charsets(collation, args, arg_count, MY_COLL_ALLOW_CONV);
unknown's avatar
unknown committed
1896 1897 1898 1899 1900 1901 1902 1903 1904
    break;
  case DECIMAL_RESULT:
    count_decimal_length();
    break;
  case REAL_RESULT:
    count_real_length();
    break;
  case INT_RESULT:
    count_only_length();
1905
    decimals= 0;
unknown's avatar
unknown committed
1906 1907
    break;
  case ROW_RESULT:
1908
  default:
unknown's avatar
unknown committed
1909 1910
    DBUG_ASSERT(0);
  }
unknown's avatar
unknown committed
1911 1912 1913
}

/****************************************************************************
1914
 Classes and function for the IN operator
unknown's avatar
unknown committed
1915 1916
****************************************************************************/

1917
static int cmp_longlong(void *cmp_arg, longlong *a,longlong *b)
unknown's avatar
unknown committed
1918 1919 1920 1921
{
  return *a < *b ? -1 : *a == *b ? 0 : 1;
}

1922
static int cmp_double(void *cmp_arg, double *a,double *b)
unknown's avatar
unknown committed
1923 1924 1925 1926
{
  return *a < *b ? -1 : *a == *b ? 0 : 1;
}

unknown's avatar
unknown committed
1927
static int cmp_row(void *cmp_arg, cmp_item_row *a, cmp_item_row *b)
unknown's avatar
unknown committed
1928 1929 1930 1931
{
  return a->compare(b);
}

unknown's avatar
unknown committed
1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944

static int cmp_decimal(void *cmp_arg, my_decimal *a, my_decimal *b)
{
  /*
    We need call of fixing buffer pointer, because fast sort just copy
    decimal buffers in memory and pointers left pointing on old buffer place
  */
  a->fix_buffer_pointer();
  b->fix_buffer_pointer();
  return my_decimal_cmp(a, b);
}


unknown's avatar
unknown committed
1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956
int in_vector::find(Item *item)
{
  byte *result=get_value(item);
  if (!result || !used_count)
    return 0;				// Null value

  uint start,end;
  start=0; end=used_count-1;
  while (start != end)
  {
    uint mid=(start+end+1)/2;
    int res;
1957
    if ((res=(*compare)(collation, base+mid*size, result)) == 0)
unknown's avatar
unknown committed
1958 1959 1960 1961 1962 1963
      return 1;
    if (res < 0)
      start=mid;
    else
      end=mid-1;
  }
1964
  return (int) ((*compare)(collation, base+start*size, result) == 0);
unknown's avatar
unknown committed
1965 1966
}

1967 1968
in_string::in_string(uint elements,qsort2_cmp cmp_func, CHARSET_INFO *cs)
  :in_vector(elements, sizeof(String), cmp_func, cs),
1969
   tmp(buff, sizeof(buff), &my_charset_bin)
unknown's avatar
unknown committed
1970 1971 1972 1973
{}

in_string::~in_string()
{
1974
  if (base)
1975
  {
unknown's avatar
unknown committed
1976
    // base was allocated with help of sql_alloc => following is OK
1977 1978
    for (uint i=0 ; i < count ; i++)
      ((String*) base)[i].free();
1979
  }
unknown's avatar
unknown committed
1980 1981 1982 1983 1984 1985 1986
}

void in_string::set(uint pos,Item *item)
{
  String *str=((String*) base)+pos;
  String *res=item->val_str(str);
  if (res && res != str)
1987 1988 1989
  {
    if (res->uses_buffer_owned_by(str))
      res->copy();
unknown's avatar
unknown committed
1990
    *str= *res;
1991
  }
1992
  if (!str->charset())
1993 1994
  {
    CHARSET_INFO *cs;
1995
    if (!(cs= item->collation.collation))
1996
      cs= &my_charset_bin;		// Should never happen for STR items
1997 1998
    str->set_charset(cs);
  }
unknown's avatar
unknown committed
1999 2000
}

2001

unknown's avatar
unknown committed
2002 2003 2004 2005 2006
byte *in_string::get_value(Item *item)
{
  return (byte*) item->val_str(&tmp);
}

unknown's avatar
unknown committed
2007 2008
in_row::in_row(uint elements, Item * item)
{
2009
  base= (char*) new cmp_item_row[count= elements];
unknown's avatar
unknown committed
2010
  size= sizeof(cmp_item_row);
2011
  compare= (qsort2_cmp) cmp_row;
unknown's avatar
unknown committed
2012
  tmp.store_value(item);
2013 2014 2015 2016 2017 2018
  /*
    We need to reset these as otherwise we will call sort() with
    uninitialized (even if not used) elements
  */
  used_count= elements;
  collation= 0;
2019 2020 2021 2022 2023
}

in_row::~in_row()
{
  if (base)
2024
    delete [] (cmp_item_row*) base;
unknown's avatar
unknown committed
2025 2026 2027 2028 2029
}

byte *in_row::get_value(Item *item)
{
  tmp.store_value(item);
unknown's avatar
unknown committed
2030 2031
  if (item->is_null())
    return 0;
unknown's avatar
unknown committed
2032 2033 2034 2035 2036 2037 2038 2039 2040 2041
  return (byte *)&tmp;
}

void in_row::set(uint pos, Item *item)
{
  DBUG_ENTER("in_row::set");
  DBUG_PRINT("enter", ("pos %u item 0x%lx", pos, (ulong) item));
  ((cmp_item_row*) base)[pos].store_value_by_template(&tmp, item);
  DBUG_VOID_RETURN;
}
unknown's avatar
unknown committed
2042 2043

in_longlong::in_longlong(uint elements)
2044
  :in_vector(elements,sizeof(longlong),(qsort2_cmp) cmp_longlong, 0)
unknown's avatar
unknown committed
2045 2046 2047 2048 2049 2050 2051 2052 2053
{}

void in_longlong::set(uint pos,Item *item)
{
  ((longlong*) base)[pos]=item->val_int();
}

byte *in_longlong::get_value(Item *item)
{
unknown's avatar
unknown committed
2054
  tmp= item->val_int();
unknown's avatar
unknown committed
2055
  if (item->null_value)
unknown's avatar
unknown committed
2056
    return 0;
unknown's avatar
unknown committed
2057 2058 2059 2060
  return (byte*) &tmp;
}

in_double::in_double(uint elements)
2061
  :in_vector(elements,sizeof(double),(qsort2_cmp) cmp_double, 0)
unknown's avatar
unknown committed
2062 2063 2064 2065
{}

void in_double::set(uint pos,Item *item)
{
2066
  ((double*) base)[pos]= item->val_real();
unknown's avatar
unknown committed
2067 2068 2069 2070
}

byte *in_double::get_value(Item *item)
{
2071
  tmp= item->val_real();
unknown's avatar
unknown committed
2072
  if (item->null_value)
2073
    return 0;					/* purecov: inspected */
unknown's avatar
unknown committed
2074 2075 2076
  return (byte*) &tmp;
}

unknown's avatar
unknown committed
2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105

in_decimal::in_decimal(uint elements)
  :in_vector(elements, sizeof(my_decimal),(qsort2_cmp) cmp_decimal, 0)
{}


void in_decimal::set(uint pos, Item *item)
{
  /* as far as 'item' is constant, we can store reference on my_decimal */
  my_decimal *dec= ((my_decimal *)base) + pos;
  dec->len= DECIMAL_BUFF_LENGTH;
  dec->fix_buffer_pointer();
  my_decimal *res= item->val_decimal(dec);
  if (res != dec)
    my_decimal2decimal(res, dec);
}


byte *in_decimal::get_value(Item *item)
{
  my_decimal *result= item->val_decimal(&val);
  if (item->null_value)
    return 0;
  return (byte *)result;
}


cmp_item* cmp_item::get_comparator(Item_result type,
                                   CHARSET_INFO *cs)
2106
{
unknown's avatar
unknown committed
2107
  switch (type) {
2108
  case STRING_RESULT:
unknown's avatar
unknown committed
2109
    return new cmp_item_sort_string(cs);
2110 2111 2112 2113 2114 2115
  case INT_RESULT:
    return new cmp_item_int;
  case REAL_RESULT:
    return new cmp_item_real;
  case ROW_RESULT:
    return new cmp_item_row;
unknown's avatar
unknown committed
2116 2117
  case DECIMAL_RESULT:
    return new cmp_item_decimal;
unknown's avatar
unknown committed
2118 2119 2120
  default:
    DBUG_ASSERT(0);
    break;
2121 2122 2123 2124
  }
  return 0; // to satisfy compiler :)
}

2125

unknown's avatar
unknown committed
2126 2127
cmp_item* cmp_item_sort_string::make_same()
{
2128
  return new cmp_item_sort_string_in_static(cmp_charset);
unknown's avatar
unknown committed
2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145
}

cmp_item* cmp_item_int::make_same()
{
  return new cmp_item_int();
}

cmp_item* cmp_item_real::make_same()
{
  return new cmp_item_real();
}

cmp_item* cmp_item_row::make_same()
{
  return new cmp_item_row();
}

2146 2147 2148 2149

cmp_item_row::~cmp_item_row()
{
  DBUG_ENTER("~cmp_item_row");
2150
  DBUG_PRINT("enter",("this: 0x%lx", this));
2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
  if (comparators)
  {
    for (uint i= 0; i < n; i++)
    {
      if (comparators[i])
	delete comparators[i];
    }
  }
  DBUG_VOID_RETURN;
}


2163 2164
void cmp_item_row::store_value(Item *item)
{
2165
  DBUG_ENTER("cmp_item_row::store_value");
2166
  n= item->cols();
2167
  if (!comparators)
unknown's avatar
unknown committed
2168
    comparators= (cmp_item **) current_thd->calloc(sizeof(cmp_item *)*n);
2169
  if (comparators)
2170
  {
2171
    item->bring_value();
unknown's avatar
unknown committed
2172
    item->null_value= 0;
2173
    for (uint i=0; i < n; i++)
2174
    {
unknown's avatar
unknown committed
2175
      if (!comparators[i])
unknown's avatar
unknown committed
2176 2177 2178
        if (!(comparators[i]=
              cmp_item::get_comparator(item->el(i)->result_type(),
                                       item->el(i)->collation.collation)))
unknown's avatar
unknown committed
2179
	  break;					// new failed
2180 2181 2182
      comparators[i]->store_value(item->el(i));
      item->null_value|= item->el(i)->null_value;
    }
2183
  }
2184
  DBUG_VOID_RETURN;
2185 2186
}

2187

unknown's avatar
unknown committed
2188 2189 2190 2191 2192
void cmp_item_row::store_value_by_template(cmp_item *t, Item *item)
{
  cmp_item_row *tmpl= (cmp_item_row*) t;
  if (tmpl->n != item->cols())
  {
unknown's avatar
unknown committed
2193
    my_error(ER_OPERAND_COLUMNS, MYF(0), tmpl->n);
unknown's avatar
unknown committed
2194 2195 2196 2197 2198
    return;
  }
  n= tmpl->n;
  if ((comparators= (cmp_item **) sql_alloc(sizeof(cmp_item *)*n)))
  {
2199
    item->bring_value();
unknown's avatar
unknown committed
2200 2201
    item->null_value= 0;
    for (uint i=0; i < n; i++)
2202 2203 2204 2205 2206 2207 2208
    {
      if (!(comparators[i]= tmpl->comparators[i]->make_same()))
	break;					// new failed
      comparators[i]->store_value_by_template(tmpl->comparators[i],
					      item->el(i));
      item->null_value|= item->el(i)->null_value;
    }
unknown's avatar
unknown committed
2209 2210 2211
  }
}

2212

2213 2214
int cmp_item_row::cmp(Item *arg)
{
unknown's avatar
unknown committed
2215 2216 2217
  arg->null_value= 0;
  if (arg->cols() != n)
  {
unknown's avatar
unknown committed
2218
    my_error(ER_OPERAND_COLUMNS, MYF(0), n);
unknown's avatar
unknown committed
2219 2220
    return 1;
  }
unknown's avatar
unknown committed
2221
  bool was_null= 0;
2222
  arg->bring_value();
unknown's avatar
unknown committed
2223
  for (uint i=0; i < n; i++)
2224
  {
unknown's avatar
unknown committed
2225
    if (comparators[i]->cmp(arg->el(i)))
unknown's avatar
unknown committed
2226
    {
unknown's avatar
unknown committed
2227 2228 2229
      if (!arg->el(i)->null_value)
	return 1;
      was_null= 1;
unknown's avatar
unknown committed
2230
    }
2231
  }
unknown's avatar
unknown committed
2232
  return (arg->null_value= was_null);
unknown's avatar
unknown committed
2233 2234
}

2235

unknown's avatar
unknown committed
2236 2237 2238
int cmp_item_row::compare(cmp_item *c)
{
  cmp_item_row *cmp= (cmp_item_row *) c;
unknown's avatar
unknown committed
2239
  for (uint i=0; i < n; i++)
2240 2241
  {
    int res;
unknown's avatar
unknown committed
2242
    if ((res= comparators[i]->compare(cmp->comparators[i])))
unknown's avatar
unknown committed
2243
      return res;
2244
  }
2245 2246
  return 0;
}
unknown's avatar
unknown committed
2247

2248

unknown's avatar
unknown committed
2249 2250 2251
void cmp_item_decimal::store_value(Item *item)
{
  my_decimal *val= item->val_decimal(&value);
unknown's avatar
unknown committed
2252 2253
  /* val may be zero if item is nnull */
  if (val && val != &value)
unknown's avatar
unknown committed
2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266
    my_decimal2decimal(val, &value);
}


int cmp_item_decimal::cmp(Item *arg)
{
  my_decimal tmp_buf, *tmp= arg->val_decimal(&tmp_buf);
  if (arg->null_value)
    return 1;
  return my_decimal_cmp(&value, tmp);
}


unknown's avatar
unknown committed
2267
int cmp_item_decimal::compare(cmp_item *arg)
unknown's avatar
unknown committed
2268
{
unknown's avatar
unknown committed
2269
  cmp_item_decimal *cmp= (cmp_item_decimal*) arg;
unknown's avatar
unknown committed
2270 2271 2272 2273 2274 2275 2276 2277 2278 2279
  return my_decimal_cmp(&value, &cmp->value);
}


cmp_item* cmp_item_decimal::make_same()
{
  return new cmp_item_decimal();
}


unknown's avatar
unknown committed
2280 2281 2282
bool Item_func_in::nulls_in_row()
{
  Item **arg,**arg_end;
2283
  for (arg= args+1, arg_end= args+arg_count; arg != arg_end ; arg++)
unknown's avatar
unknown committed
2284 2285 2286 2287 2288 2289 2290
  {
    if ((*arg)->null_inside())
      return 1;
  }
  return 0;
}

2291

unknown's avatar
unknown committed
2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321
/*
  Perform context analysis of an IN item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_in as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(e IN(e1,...,en))     = union(T1(e),intersection(T1(ei)))
      T1(e IN(e1,...,en))     = union(T1(e),intersection(T1(ei)))
      T0(e NOT IN(e1,...,en)) = union(T1(e),union(T1(ei)))
      T1(e NOT IN(e1,...,en)) = union(T1(e),intersection(T1(ei)))

  RETURN
    0   ok
    1   got error
*/

bool
2322
Item_func_in::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
2323 2324 2325
{
  Item **arg, **arg_end;

2326
  if (Item_func_opt_neg::fix_fields(thd, ref))
unknown's avatar
unknown committed
2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341
    return 1;

  /* not_null_tables_cache == union(T1(e),union(T1(ei))) */
  if (pred_level && negated)
    return 0;

  /* not_null_tables_cache = union(T1(e),intersection(T1(ei))) */
  not_null_tables_cache= ~(table_map) 0;
  for (arg= args + 1, arg_end= args + arg_count; arg != arg_end; arg++)
    not_null_tables_cache&= (*arg)->not_null_tables();
  not_null_tables_cache|= (*args)->not_null_tables();
  return 0;
}


2342
static int srtcmp_in(CHARSET_INFO *cs, const String *x,const String *y)
2343
{
2344
  return cs->coll->strnncollsp(cs,
unknown's avatar
unknown committed
2345
                               (uchar *) x->ptr(),x->length(),
2346
                               (uchar *) y->ptr(),y->length(), 0);
2347 2348
}

2349

unknown's avatar
unknown committed
2350 2351
void Item_func_in::fix_length_and_dec()
{
2352 2353
  Item **arg, **arg_end;
  uint const_itm= 1;
2354
  THD *thd= current_thd;
2355
  
2356
  agg_cmp_type(thd, &cmp_type, args, arg_count);
2357

unknown's avatar
unknown committed
2358 2359 2360 2361
  if (cmp_type == STRING_RESULT &&
      agg_arg_charsets(cmp_collation, args, arg_count, MY_COLL_CMP_CONV))
    return;

2362
  for (arg=args+1, arg_end=args+arg_count; arg != arg_end ; arg++)
unknown's avatar
unknown committed
2363 2364 2365 2366 2367 2368 2369
  {
    if (!arg[0]->const_item())
    {
      const_itm= 0;
      break;
    }
  }
2370

unknown's avatar
unknown committed
2371 2372 2373 2374
  /*
    Row item with NULLs inside can return NULL or FALSE => 
    they can't be processed as static
  */
2375
  if (const_itm && !nulls_in_row())
unknown's avatar
unknown committed
2376
  {
2377
    switch (cmp_type) {
unknown's avatar
unknown committed
2378
    case STRING_RESULT:
2379
      array=new in_string(arg_count-1,(qsort2_cmp) srtcmp_in, 
2380
			  cmp_collation.collation);
unknown's avatar
unknown committed
2381 2382
      break;
    case INT_RESULT:
2383
      array= new in_longlong(arg_count-1);
unknown's avatar
unknown committed
2384 2385
      break;
    case REAL_RESULT:
2386
      array= new in_double(arg_count-1);
unknown's avatar
unknown committed
2387
      break;
unknown's avatar
unknown committed
2388
    case ROW_RESULT:
2389
      array= new in_row(arg_count-1, args[0]);
unknown's avatar
unknown committed
2390
      break;
unknown's avatar
unknown committed
2391 2392 2393
    case DECIMAL_RESULT:
      array= new in_decimal(arg_count - 1);
      break;
unknown's avatar
unknown committed
2394 2395 2396
    default:
      DBUG_ASSERT(0);
      return;
unknown's avatar
unknown committed
2397
    }
2398
    if (array && !(thd->is_fatal_error))		// If not EOM
unknown's avatar
unknown committed
2399
    {
unknown's avatar
unknown committed
2400
      uint j=0;
unknown's avatar
unknown committed
2401
      for (uint i=1 ; i < arg_count ; i++)
unknown's avatar
unknown committed
2402 2403 2404 2405
      {
	array->set(j,args[i]);
	if (!args[i]->null_value)			// Skip NULL values
	  j++;
unknown's avatar
unknown committed
2406 2407
	else
	  have_null= 1;
unknown's avatar
unknown committed
2408 2409 2410
      }
      if ((array->used_count=j))
	array->sort();
unknown's avatar
unknown committed
2411 2412 2413 2414
    }
  }
  else
  {
unknown's avatar
unknown committed
2415
    in_item= cmp_item::get_comparator(cmp_type, cmp_collation.collation);
2416
    if (cmp_type  == STRING_RESULT)
2417
      in_item->cmp_charset= cmp_collation.collation;
unknown's avatar
unknown committed
2418
  }
2419
  maybe_null= args[0]->maybe_null;
unknown's avatar
unknown committed
2420
  max_length= 1;
unknown's avatar
unknown committed
2421 2422 2423 2424 2425 2426
}


void Item_func_in::print(String *str)
{
  str->append('(');
2427
  args[0]->print(str);
unknown's avatar
unknown committed
2428
  if (negated)
2429 2430
    str->append(STRING_WITH_LEN(" not"));
  str->append(STRING_WITH_LEN(" in ("));
unknown's avatar
unknown committed
2431
  print_args(str, 1);
2432
  str->append(STRING_WITH_LEN("))"));
unknown's avatar
unknown committed
2433 2434 2435 2436 2437
}


longlong Item_func_in::val_int()
{
2438
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2439 2440
  if (array)
  {
2441 2442
    int tmp=array->find(args[0]);
    null_value=args[0]->null_value || (!tmp && have_null);
unknown's avatar
unknown committed
2443
    return (longlong) (!null_value && tmp != negated);
unknown's avatar
unknown committed
2444
  }
2445 2446
  in_item->store_value(args[0]);
  if ((null_value=args[0]->null_value))
unknown's avatar
unknown committed
2447
    return 0;
2448
  have_null= 0;
2449
  for (uint i=1 ; i < arg_count ; i++)
unknown's avatar
unknown committed
2450 2451
  {
    if (!in_item->cmp(args[i]) && !args[i]->null_value)
unknown's avatar
unknown committed
2452
      return (longlong) (!negated);
2453
    have_null|= args[i]->null_value;
unknown's avatar
unknown committed
2454
  }
2455
  null_value= have_null;
unknown's avatar
unknown committed
2456
  return (longlong) (!null_value && negated);
unknown's avatar
unknown committed
2457 2458 2459 2460 2461
}


longlong Item_func_bit_or::val_int()
{
2462
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481
  ulonglong arg1= (ulonglong) args[0]->val_int();
  if (args[0]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  ulonglong arg2= (ulonglong) args[1]->val_int();
  if (args[1]->null_value)
  {
    null_value=1;
    return 0;
  }
  null_value=0;
  return (longlong) (arg1 | arg2);
}


longlong Item_func_bit_and::val_int()
{
2482
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498
  ulonglong arg1= (ulonglong) args[0]->val_int();
  if (args[0]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  ulonglong arg2= (ulonglong) args[1]->val_int();
  if (args[1]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  null_value=0;
  return (longlong) (arg1 & arg2);
}

2499
Item_cond::Item_cond(THD *thd, Item_cond *item)
2500
  :Item_bool_func(thd, item),
2501 2502
   abort_on_null(item->abort_on_null),
   and_tables_cache(item->and_tables_cache)
2503 2504
{
  /*
unknown's avatar
unknown committed
2505
    item->list will be copied by copy_andor_arguments() call
2506 2507 2508
  */
}

unknown's avatar
unknown committed
2509

2510 2511 2512
void Item_cond::copy_andor_arguments(THD *thd, Item_cond *item)
{
  List_iterator_fast<Item> li(item->list);
unknown's avatar
unknown committed
2513
  while (Item *it= li++)
2514 2515
    list.push_back(it->copy_andor_structure(thd));
}
unknown's avatar
unknown committed
2516

unknown's avatar
unknown committed
2517

unknown's avatar
unknown committed
2518
bool
2519
Item_cond::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
2520
{
2521
  DBUG_ASSERT(fixed == 0);
unknown's avatar
unknown committed
2522 2523
  List_iterator<Item> li(list);
  Item *item;
2524
#ifndef EMBEDDED_LIBRARY
unknown's avatar
unknown committed
2525
  char buff[sizeof(char*)];			// Max local vars in function
2526
#endif
2527
  not_null_tables_cache= used_tables_cache= 0;
unknown's avatar
unknown committed
2528
  const_item_cache= 1;
2529 2530 2531 2532 2533
  /*
    and_table_cache is the value that Item_cond_or() returns for
    not_null_tables()
  */
  and_tables_cache= ~(table_map) 0;
unknown's avatar
unknown committed
2534

2535
  if (check_stack_overrun(thd, STACK_MIN_SIZE, buff))
unknown's avatar
unknown committed
2536
    return TRUE;				// Fatal error flag is set!
2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551
  /*
    The following optimization reduces the depth of an AND-OR tree.
    E.g. a WHERE clause like
      F1 AND (F2 AND (F2 AND F4))
    is parsed into a tree with the same nested structure as defined
    by braces. This optimization will transform such tree into
      AND (F1, F2, F3, F4).
    Trees of OR items are flattened as well:
      ((F1 OR F2) OR (F3 OR F4))   =>   OR (F1, F2, F3, F4)
    Items for removed AND/OR levels will dangle until the death of the
    entire statement.
    The optimization is currently prepared statements and stored procedures
    friendly as it doesn't allocate any memory and its effects are durable
    (i.e. do not depend on PS/SP arguments).
  */
unknown's avatar
unknown committed
2552 2553
  while ((item=li++))
  {
2554
    table_map tmp_table_map;
unknown's avatar
unknown committed
2555 2556 2557 2558 2559 2560 2561
    while (item->type() == Item::COND_ITEM &&
	   ((Item_cond*) item)->functype() == functype())
    {						// Identical function
      li.replace(((Item_cond*) item)->list);
      ((Item_cond*) item)->list.empty();
      item= *li.ref();				// new current item
    }
2562 2563
    if (abort_on_null)
      item->top_level_item();
2564 2565

    // item can be substituted in fix_fields
2566
    if ((!item->fixed &&
2567
	 item->fix_fields(thd, li.ref())) ||
2568
	(item= *li.ref())->check_cols(1))
unknown's avatar
unknown committed
2569
      return TRUE; /* purecov: inspected */
2570 2571 2572 2573
    used_tables_cache|=     item->used_tables();
    tmp_table_map=	    item->not_null_tables();
    not_null_tables_cache|= tmp_table_map;
    and_tables_cache&=      tmp_table_map;
unknown's avatar
unknown committed
2574
    const_item_cache&=      item->const_item();
2575
    with_sum_func=	    with_sum_func || item->with_sum_func;
unknown's avatar
unknown committed
2576 2577
    if (item->maybe_null)
      maybe_null=1;
unknown's avatar
unknown committed
2578
  }
2579
  thd->lex->current_select->cond_count+= list.elements;
unknown's avatar
unknown committed
2580
  fix_length_and_dec();
2581
  fixed= 1;
unknown's avatar
unknown committed
2582
  return FALSE;
unknown's avatar
unknown committed
2583 2584
}

unknown's avatar
unknown committed
2585 2586 2587 2588 2589 2590 2591 2592 2593 2594
bool Item_cond::walk(Item_processor processor, byte *arg)
{
  List_iterator_fast<Item> li(list);
  Item *item;
  while ((item= li++))
    if (item->walk(processor, arg))
      return 1;
  return Item_func::walk(processor, arg);
}

unknown's avatar
unknown committed
2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606

/*
  Transform an Item_cond object with a transformer callback function
   
  SYNOPSIS
    transform()
    transformer   the transformer callback function to be applied to the nodes
                  of the tree of the object
    arg           parameter to be passed to the transformer
  
  DESCRIPTION
    The function recursively applies the transform method with the
unknown's avatar
unknown committed
2607
    same transformer to each member item of the condition list.
unknown's avatar
unknown committed
2608 2609 2610 2611 2612 2613 2614 2615 2616 2617
    If the call of the method for a member item returns a new item
    the old item is substituted for a new one.
    After this the transform method is applied to the root node
    of the Item_cond object. 
     
  RETURN VALUES
    Item returned as the result of transformation of the root node 
*/

Item *Item_cond::transform(Item_transformer transformer, byte *arg)
2618 2619 2620 2621 2622
{
  List_iterator<Item> li(list);
  Item *item;
  while ((item= li++))
  {
unknown's avatar
unknown committed
2623
    Item *new_item= item->transform(transformer, arg);
2624 2625 2626 2627 2628
    if (!new_item)
      return 0;
    if (new_item != item)
      li.replace(new_item);
  }
unknown's avatar
unknown committed
2629
  return Item_func::transform(transformer, arg);
2630 2631
}

2632 2633
void Item_cond::traverse_cond(Cond_traverser traverser,
                              void *arg, traverse_order order)
2634 2635 2636 2637
{
  List_iterator<Item> li(list);
  Item *item;

2638 2639 2640 2641 2642 2643 2644
  switch(order) {
  case(PREFIX):
    (*traverser)(this, arg);
    while ((item= li++))
    {
      item->traverse_cond(traverser, arg, order);
    }
2645
    (*traverser)(NULL, arg);
2646 2647 2648 2649 2650 2651 2652
    break;
  case(POSTFIX):
    while ((item= li++))
    {
      item->traverse_cond(traverser, arg, order);
    }
    (*traverser)(this, arg);
2653 2654
  }
}
unknown's avatar
unknown committed
2655

2656 2657 2658 2659
/*
  Move SUM items out from item tree and replace with reference

  SYNOPSIS
2660 2661 2662 2663
    split_sum_func()
    thd			Thread handler
    ref_pointer_array	Pointer to array of reference fields
    fields		All fields in select
2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674

  NOTES
   This function is run on all expression (SELECT list, WHERE, HAVING etc)
   that have or refer (HAVING) to a SUM expression.

   The split is done to get an unique item for each SUM function
   so that we can easily find and calculate them.
   (Calculation done by update_sum_func() and copy_sum_funcs() in
   sql_select.cc)
*/

2675 2676
void Item_cond::split_sum_func(THD *thd, Item **ref_pointer_array,
                               List<Item> &fields)
unknown's avatar
unknown committed
2677 2678 2679
{
  List_iterator<Item> li(list);
  Item *item;
2680
  while ((item= li++))
unknown's avatar
unknown committed
2681
    item->split_sum_func2(thd, ref_pointer_array, fields, li.ref(), TRUE);
unknown's avatar
unknown committed
2682 2683 2684 2685 2686 2687 2688 2689 2690
}


table_map
Item_cond::used_tables() const
{						// This caches used_tables
  return used_tables_cache;
}

2691

unknown's avatar
unknown committed
2692 2693
void Item_cond::update_used_tables()
{
unknown's avatar
unknown committed
2694
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
2695
  Item *item;
2696 2697 2698

  used_tables_cache=0;
  const_item_cache=1;
unknown's avatar
unknown committed
2699 2700 2701
  while ((item=li++))
  {
    item->update_used_tables();
2702
    used_tables_cache|= item->used_tables();
unknown's avatar
unknown committed
2703
    const_item_cache&= item->const_item();
unknown's avatar
unknown committed
2704 2705 2706 2707 2708 2709 2710
  }
}


void Item_cond::print(String *str)
{
  str->append('(');
unknown's avatar
unknown committed
2711
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724
  Item *item;
  if ((item=li++))
    item->print(str);
  while ((item=li++))
  {
    str->append(' ');
    str->append(func_name());
    str->append(' ');
    item->print(str);
  }
  str->append(')');
}

2725

2726
void Item_cond::neg_arguments(THD *thd)
2727 2728 2729 2730 2731
{
  List_iterator<Item> li(list);
  Item *item;
  while ((item= li++))		/* Apply not transformation to the arguments */
  {
2732 2733 2734
    Item *new_item= item->neg_transformer(thd);
    if (!new_item)
    {
unknown's avatar
unknown committed
2735 2736
      if (!(new_item= new Item_func_not(item)))
	return;					// Fatal OEM error
2737 2738
    }
    VOID(li.replace(new_item));
2739 2740 2741 2742
  }
}


2743
/*
unknown's avatar
unknown committed
2744
  Evaluation of AND(expr, expr, expr ...)
2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759

  NOTES:
    abort_if_null is set for AND expressions for which we don't care if the
    result is NULL or 0. This is set for:
    - WHERE clause
    - HAVING clause
    - IF(expression)

  RETURN VALUES
    1  If all expressions are true
    0  If all expressions are false or if we find a NULL expression and
       'abort_on_null' is set.
    NULL if all expression are either 1 or NULL
*/

unknown's avatar
unknown committed
2760 2761 2762

longlong Item_cond_and::val_int()
{
2763
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2764
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
2765
  Item *item;
2766
  null_value= 0;
unknown's avatar
unknown committed
2767 2768
  while ((item=li++))
  {
unknown's avatar
unknown committed
2769
    if (!item->val_bool())
unknown's avatar
unknown committed
2770
    {
2771 2772
      if (abort_on_null || !(null_value= item->null_value))
	return 0;				// return FALSE
unknown's avatar
unknown committed
2773 2774
    }
  }
2775
  return null_value ? 0 : 1;
unknown's avatar
unknown committed
2776 2777
}

2778

unknown's avatar
unknown committed
2779 2780
longlong Item_cond_or::val_int()
{
2781
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2782
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
2783 2784 2785 2786
  Item *item;
  null_value=0;
  while ((item=li++))
  {
unknown's avatar
unknown committed
2787
    if (item->val_bool())
unknown's avatar
unknown committed
2788 2789 2790 2791 2792 2793 2794 2795 2796 2797
    {
      null_value=0;
      return 1;
    }
    if (item->null_value)
      null_value=1;
  }
  return 0;
}

2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821
/*
  Create an AND expression from two expressions

  SYNOPSIS
   and_expressions()
   a		expression or NULL
   b    	expression.
   org_item	Don't modify a if a == *org_item
		If a == NULL, org_item is set to point at b,
		to ensure that future calls will not modify b.

  NOTES
    This will not modify item pointed to by org_item or b
    The idea is that one can call this in a loop and create and
    'and' over all items without modifying any of the original items.

  RETURN
    NULL	Error
    Item
*/

Item *and_expressions(Item *a, Item *b, Item **org_item)
{
  if (!a)
2822
    return (*org_item= (Item*) b);
2823 2824 2825
  if (a == *org_item)
  {
    Item_cond *res;
2826
    if ((res= new Item_cond_and(a, (Item*) b)))
2827
    {
2828
      res->used_tables_cache= a->used_tables() | b->used_tables();
2829 2830
      res->not_null_tables_cache= a->not_null_tables() | b->not_null_tables();
    }
2831 2832
    return res;
  }
2833
  if (((Item_cond_and*) a)->add((Item*) b))
2834 2835
    return 0;
  ((Item_cond_and*) a)->used_tables_cache|= b->used_tables();
2836
  ((Item_cond_and*) a)->not_null_tables_cache|= b->not_null_tables();
2837 2838 2839 2840
  return a;
}


unknown's avatar
unknown committed
2841 2842
longlong Item_func_isnull::val_int()
{
2843
  DBUG_ASSERT(fixed == 1);
2844 2845 2846 2847 2848
  /*
    Handle optimization if the argument can't be null
    This has to be here because of the test in update_used_tables().
  */
  if (!used_tables_cache)
unknown's avatar
unknown committed
2849
    return cached_value;
unknown's avatar
unknown committed
2850
  return args[0]->is_null() ? 1: 0;
unknown's avatar
unknown committed
2851 2852
}

2853 2854
longlong Item_is_not_null_test::val_int()
{
2855
  DBUG_ASSERT(fixed == 1);
2856 2857 2858 2859 2860 2861 2862 2863 2864
  DBUG_ENTER("Item_is_not_null_test::val_int");
  if (!used_tables_cache)
  {
    owner->was_null|= (!cached_value);
    DBUG_PRINT("info", ("cached :%d", cached_value));
    DBUG_RETURN(cached_value);
  }
  if (args[0]->is_null())
  {
unknown's avatar
unknown committed
2865
    DBUG_PRINT("info", ("null"));
2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890
    owner->was_null|= 1;
    DBUG_RETURN(0);
  }
  else
    DBUG_RETURN(1);
}

/* Optimize case of not_null_column IS NULL */
void Item_is_not_null_test::update_used_tables()
{
  if (!args[0]->maybe_null)
  {
    used_tables_cache= 0;			/* is always true */
    cached_value= (longlong) 1;
  }
  else
  {
    args[0]->update_used_tables();
    if (!(used_tables_cache=args[0]->used_tables()))
    {
      /* Remember if the value is always NULL or never NULL */
      cached_value= (longlong) !args[0]->is_null();
    }
  }
}
2891

2892

unknown's avatar
unknown committed
2893 2894
longlong Item_func_isnotnull::val_int()
{
2895
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2896
  return args[0]->is_null() ? 0 : 1;
unknown's avatar
unknown committed
2897 2898 2899
}


2900 2901 2902 2903
void Item_func_isnotnull::print(String *str)
{
  str->append('(');
  args[0]->print(str);
2904
  str->append(STRING_WITH_LEN(" is not null)"));
2905 2906 2907
}


unknown's avatar
unknown committed
2908 2909
longlong Item_func_like::val_int()
{
2910
  DBUG_ASSERT(fixed == 1);
2911
  String* res = args[0]->val_str(&tmp_value1);
unknown's avatar
unknown committed
2912 2913 2914 2915 2916
  if (args[0]->null_value)
  {
    null_value=1;
    return 0;
  }
2917
  String* res2 = args[1]->val_str(&tmp_value2);
unknown's avatar
unknown committed
2918 2919 2920 2921 2922 2923
  if (args[1]->null_value)
  {
    null_value=1;
    return 0;
  }
  null_value=0;
2924 2925
  if (canDoTurboBM)
    return turboBM_matches(res->ptr(), res->length()) ? 1 : 0;
2926
  return my_wildcmp(cmp.cmp_collation.collation,
2927 2928 2929
		    res->ptr(),res->ptr()+res->length(),
		    res2->ptr(),res2->ptr()+res2->length(),
		    escape,wild_one,wild_many) ? 0 : 1;
unknown's avatar
unknown committed
2930 2931 2932 2933 2934 2935 2936
}


/* We can optimize a where if first character isn't a wildcard */

Item_func::optimize_type Item_func_like::select_optimize() const
{
2937
  if (args[1]->const_item())
unknown's avatar
unknown committed
2938
  {
2939 2940 2941 2942 2943 2944
    String* res2= args[1]->val_str((String *)&tmp_value2);

    if (!res2)
      return OPTIMIZE_NONE;

    if (*res2->ptr() != wild_many)
unknown's avatar
unknown committed
2945
    {
2946
      if (args[0]->result_type() != STRING_RESULT || *res2->ptr() != wild_one)
unknown's avatar
unknown committed
2947 2948 2949 2950 2951 2952
	return OPTIMIZE_OP;
    }
  }
  return OPTIMIZE_NONE;
}

2953

2954
bool Item_func_like::fix_fields(THD *thd, Item **ref)
2955
{
2956
  DBUG_ASSERT(fixed == 0);
2957 2958
  if (Item_bool_func2::fix_fields(thd, ref) ||
      escape_item->fix_fields(thd, &escape_item))
unknown's avatar
unknown committed
2959
    return TRUE;
2960

2961
  if (!escape_item->const_during_execution())
2962
  {
2963
    my_error(ER_WRONG_ARGUMENTS,MYF(0),"ESCAPE");
unknown's avatar
unknown committed
2964
    return TRUE;
2965 2966 2967 2968 2969 2970
  }
  
  if (escape_item->const_item())
  {
    /* If we are on execution stage */
    String *escape_str= escape_item->val_str(&tmp_value1);
2971 2972
    if (escape_str)
    {
2973 2974 2975 2976 2977 2978 2979 2980 2981
      if (escape_used_in_parsing && (
             (((thd->variables.sql_mode & MODE_NO_BACKSLASH_ESCAPES) &&
                escape_str->numchars() != 1) ||
               escape_str->numchars() > 1)))
      {
        my_error(ER_WRONG_ARGUMENTS,MYF(0),"ESCAPE");
        return TRUE;
      }

unknown's avatar
unknown committed
2982
      if (use_mb(cmp.cmp_collation.collation))
2983
      {
2984
        CHARSET_INFO *cs= escape_str->charset();
2985 2986 2987 2988 2989 2990 2991 2992 2993
        my_wc_t wc;
        int rc= cs->cset->mb_wc(cs, &wc,
                                (const uchar*) escape_str->ptr(),
                                (const uchar*) escape_str->ptr() +
                                               escape_str->length());
        escape= (int) (rc > 0 ? wc : '\\');
      }
      else
      {
unknown's avatar
unknown committed
2994 2995 2996 2997 2998
        /*
          In the case of 8bit character set, we pass native
          code instead of Unicode code as "escape" argument.
          Convert to "cs" if charset of escape differs.
        */
unknown's avatar
unknown committed
2999
        CHARSET_INFO *cs= cmp.cmp_collation.collation;
unknown's avatar
unknown committed
3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012
        uint32 unused;
        if (escape_str->needs_conversion(escape_str->length(),
                                         escape_str->charset(), cs, &unused))
        {
          char ch;
          uint errors;
          uint32 cnvlen= copy_and_convert(&ch, 1, cs, escape_str->ptr(),
                                          escape_str->length(),
                                          escape_str->charset(), &errors);
          escape= cnvlen ? ch : '\\';
        }
        else
          escape= *(escape_str->ptr());
3013 3014 3015 3016
      }
    }
    else
      escape= '\\';
unknown's avatar
unknown committed
3017

3018
    /*
3019 3020
      We could also do boyer-more for non-const items, but as we would have to
      recompute the tables for each row it's not worth it.
3021
    */
3022 3023
    if (args[1]->const_item() && !use_strnxfrm(collation.collation) &&
       !(specialflag & SPECIAL_NO_NEW_FUNC))
3024
    {
3025 3026
      String* res2 = args[1]->val_str(&tmp_value2);
      if (!res2)
unknown's avatar
unknown committed
3027
        return FALSE;				// Null argument
3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047
      
      const size_t len   = res2->length();
      const char*  first = res2->ptr();
      const char*  last  = first + len - 1;
      /*
        len must be > 2 ('%pattern%')
        heuristic: only do TurboBM for pattern_len > 2
      */
      
      if (len > MIN_TURBOBM_PATTERN_LEN + 2 &&
          *first == wild_many &&
          *last  == wild_many)
      {
        const char* tmp = first + 1;
        for (; *tmp != wild_many && *tmp != wild_one && *tmp != escape; tmp++) ;
        canDoTurboBM = (tmp == last) && !use_mb(args[0]->collation.collation);
      }
      if (canDoTurboBM)
      {
        pattern     = first + 1;
3048
        pattern_len = (int) len - 2;
3049
        DBUG_PRINT("info", ("Initializing pattern: '%s'", first));
3050 3051 3052
        int *suff = (int*) thd->alloc((int) (sizeof(int)*
                                      ((pattern_len + 1)*2+
                                      alphabet_size)));
3053 3054 3055 3056 3057 3058
        bmGs      = suff + pattern_len + 1;
        bmBc      = bmGs + pattern_len + 1;
        turboBM_compute_good_suffix_shifts(suff);
        turboBM_compute_bad_character_shifts();
        DBUG_PRINT("info",("done"));
      }
3059 3060
    }
  }
unknown's avatar
unknown committed
3061
  return FALSE;
3062 3063
}

3064 3065 3066 3067 3068 3069
void Item_func_like::cleanup()
{
  canDoTurboBM= FALSE;
  Item_bool_func2::cleanup();
}

unknown's avatar
unknown committed
3070 3071 3072
#ifdef USE_REGEX

bool
3073
Item_func_regex::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
3074
{
3075
  DBUG_ASSERT(fixed == 0);
unknown's avatar
unknown committed
3076
  if ((!args[0]->fixed &&
3077
       args[0]->fix_fields(thd, args)) || args[0]->check_cols(1) ||
unknown's avatar
unknown committed
3078
      (!args[1]->fixed &&
3079
       args[1]->fix_fields(thd, args + 1)) || args[1]->check_cols(1))
unknown's avatar
unknown committed
3080
    return TRUE;				/* purecov: inspected */
unknown's avatar
unknown committed
3081
  with_sum_func=args[0]->with_sum_func || args[1]->with_sum_func;
unknown's avatar
unknown committed
3082 3083
  max_length= 1;
  decimals= 0;
3084

unknown's avatar
unknown committed
3085
  if (agg_arg_charsets(cmp_collation, args, 2, MY_COLL_CMP_CONV))
unknown's avatar
unknown committed
3086
    return TRUE;
3087

unknown's avatar
unknown committed
3088
  used_tables_cache=args[0]->used_tables() | args[1]->used_tables();
3089 3090
  not_null_tables_cache= (args[0]->not_null_tables() |
			  args[1]->not_null_tables());
unknown's avatar
unknown committed
3091 3092 3093 3094
  const_item_cache=args[0]->const_item() && args[1]->const_item();
  if (!regex_compiled && args[1]->const_item())
  {
    char buff[MAX_FIELD_WIDTH];
3095
    String tmp(buff,sizeof(buff),&my_charset_bin);
unknown's avatar
unknown committed
3096 3097 3098 3099
    String *res=args[1]->val_str(&tmp);
    if (args[1]->null_value)
    {						// Will always return NULL
      maybe_null=1;
unknown's avatar
unknown committed
3100
      return FALSE;
unknown's avatar
unknown committed
3101 3102
    }
    int error;
unknown's avatar
unknown committed
3103 3104 3105 3106 3107 3108
    if ((error= my_regcomp(&preg,res->c_ptr(),
                           ((cmp_collation.collation->state &
                             (MY_CS_BINSORT | MY_CS_CSSORT)) ?
                            REG_EXTENDED | REG_NOSUB :
                            REG_EXTENDED | REG_NOSUB | REG_ICASE),
                           cmp_collation.collation)))
unknown's avatar
unknown committed
3109
    {
unknown's avatar
unknown committed
3110
      (void) my_regerror(error,&preg,buff,sizeof(buff));
3111
      my_error(ER_REGEXP_ERROR, MYF(0), buff);
unknown's avatar
unknown committed
3112
      return TRUE;
unknown's avatar
unknown committed
3113 3114 3115 3116 3117 3118
    }
    regex_compiled=regex_is_const=1;
    maybe_null=args[0]->maybe_null;
  }
  else
    maybe_null=1;
3119
  fixed= 1;
unknown's avatar
unknown committed
3120
  return FALSE;
unknown's avatar
unknown committed
3121 3122
}

3123

unknown's avatar
unknown committed
3124 3125
longlong Item_func_regex::val_int()
{
3126
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
3127
  char buff[MAX_FIELD_WIDTH];
3128
  String *res, tmp(buff,sizeof(buff),&my_charset_bin);
unknown's avatar
unknown committed
3129 3130 3131 3132 3133 3134 3135 3136 3137 3138

  res=args[0]->val_str(&tmp);
  if (args[0]->null_value)
  {
    null_value=1;
    return 0;
  }
  if (!regex_is_const)
  {
    char buff2[MAX_FIELD_WIDTH];
3139
    String *res2, tmp2(buff2,sizeof(buff2),&my_charset_bin);
unknown's avatar
unknown committed
3140 3141 3142 3143 3144 3145 3146

    res2= args[1]->val_str(&tmp2);
    if (args[1]->null_value)
    {
      null_value=1;
      return 0;
    }
unknown's avatar
unknown committed
3147
    if (!regex_compiled || stringcmp(res2,&prev_regexp))
unknown's avatar
unknown committed
3148 3149 3150 3151
    {
      prev_regexp.copy(*res2);
      if (regex_compiled)
      {
unknown's avatar
unknown committed
3152
	my_regfree(&preg);
unknown's avatar
unknown committed
3153 3154
	regex_compiled=0;
      }
unknown's avatar
Merge  
unknown committed
3155
      if (my_regcomp(&preg,res2->c_ptr_safe(),
unknown's avatar
unknown committed
3156 3157 3158 3159 3160
                     ((cmp_collation.collation->state &
                       (MY_CS_BINSORT | MY_CS_CSSORT)) ?
                      REG_EXTENDED | REG_NOSUB :
                      REG_EXTENDED | REG_NOSUB | REG_ICASE),
                     cmp_collation.collation))
unknown's avatar
unknown committed
3161 3162 3163 3164 3165 3166 3167 3168
      {
	null_value=1;
	return 0;
      }
      regex_compiled=1;
    }
  }
  null_value=0;
unknown's avatar
unknown committed
3169
  return my_regexec(&preg,res->c_ptr(),0,(my_regmatch_t*) 0,0) ? 0 : 1;
unknown's avatar
unknown committed
3170 3171 3172
}


3173
void Item_func_regex::cleanup()
unknown's avatar
unknown committed
3174
{
3175 3176
  DBUG_ENTER("Item_func_regex::cleanup");
  Item_bool_func::cleanup();
unknown's avatar
unknown committed
3177 3178
  if (regex_compiled)
  {
unknown's avatar
unknown committed
3179
    my_regfree(&preg);
unknown's avatar
unknown committed
3180 3181
    regex_compiled=0;
  }
3182
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
3183 3184
}

3185

unknown's avatar
unknown committed
3186
#endif /* USE_REGEX */
3187 3188 3189


#ifdef LIKE_CMP_TOUPPER
unknown's avatar
unknown committed
3190
#define likeconv(cs,A) (uchar) (cs)->toupper(A)
3191
#else
unknown's avatar
unknown committed
3192
#define likeconv(cs,A) (uchar) (cs)->sort_order[(uchar) (A)]
3193 3194 3195 3196 3197 3198 3199 3200
#endif


/**********************************************************************
  turboBM_compute_suffixes()
  Precomputation dependent only on pattern_len.
**********************************************************************/

3201
void Item_func_like::turboBM_compute_suffixes(int *suff)
3202 3203 3204 3205
{
  const int   plm1 = pattern_len - 1;
  int            f = 0;
  int            g = plm1;
unknown's avatar
unknown committed
3206
  int *const splm1 = suff + plm1;
3207
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
3208 3209 3210

  *splm1 = pattern_len;

unknown's avatar
unknown committed
3211
  if (!cs->sort_order)
3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242
  {
    int i;
    for (i = pattern_len - 2; i >= 0; i--)
    {
      int tmp = *(splm1 + i - f);
      if (g < i && tmp < i - g)
	suff[i] = tmp;
      else
      {
	if (i < g)
	  g = i; // g = min(i, g)
	f = i;
	while (g >= 0 && pattern[g] == pattern[g + plm1 - f])
	  g--;
	suff[i] = f - g;
      }
    }
  }
  else
  {
    int i;
    for (i = pattern_len - 2; 0 <= i; --i)
    {
      int tmp = *(splm1 + i - f);
      if (g < i && tmp < i - g)
	suff[i] = tmp;
      else
      {
	if (i < g)
	  g = i; // g = min(i, g)
	f = i;
3243
	while (g >= 0 &&
unknown's avatar
unknown committed
3244
	       likeconv(cs, pattern[g]) == likeconv(cs, pattern[g + plm1 - f]))
3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257
	  g--;
	suff[i] = f - g;
      }
    }
  }
}


/**********************************************************************
   turboBM_compute_good_suffix_shifts()
   Precomputation dependent only on pattern_len.
**********************************************************************/

3258
void Item_func_like::turboBM_compute_good_suffix_shifts(int *suff)
3259 3260 3261
{
  turboBM_compute_suffixes(suff);

3262 3263
  int *end = bmGs + pattern_len;
  int *k;
3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276
  for (k = bmGs; k < end; k++)
    *k = pattern_len;

  int tmp;
  int i;
  int j          = 0;
  const int plm1 = pattern_len - 1;
  for (i = plm1; i > -1; i--)
  {
    if (suff[i] == i + 1)
    {
      for (tmp = plm1 - i; j < tmp; j++)
      {
3277
	int *tmp2 = bmGs + j;
3278 3279 3280 3281 3282 3283
	if (*tmp2 == pattern_len)
	  *tmp2 = tmp;
      }
    }
  }

3284
  int *tmp2;
3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304
  for (tmp = plm1 - i; j < tmp; j++)
  {
    tmp2 = bmGs + j;
    if (*tmp2 == pattern_len)
      *tmp2 = tmp;
  }

  tmp2 = bmGs + plm1;
  for (i = 0; i <= pattern_len - 2; i++)
    *(tmp2 - suff[i]) = plm1 - i;
}


/**********************************************************************
   turboBM_compute_bad_character_shifts()
   Precomputation dependent on pattern_len.
**********************************************************************/

void Item_func_like::turboBM_compute_bad_character_shifts()
{
unknown's avatar
unknown committed
3305 3306 3307 3308
  int *i;
  int *end = bmBc + alphabet_size;
  int j;
  const int plm1 = pattern_len - 1;
3309
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
unknown's avatar
unknown committed
3310

3311 3312 3313
  for (i = bmBc; i < end; i++)
    *i = pattern_len;

unknown's avatar
unknown committed
3314
  if (!cs->sort_order)
unknown's avatar
unknown committed
3315
  {
3316
    for (j = 0; j < plm1; j++)
3317
      bmBc[(uint) (uchar) pattern[j]] = plm1 - j;
unknown's avatar
unknown committed
3318
  }
3319
  else
unknown's avatar
unknown committed
3320
  {
3321
    for (j = 0; j < plm1; j++)
unknown's avatar
unknown committed
3322
      bmBc[(uint) likeconv(cs,pattern[j])] = plm1 - j;
unknown's avatar
unknown committed
3323
  }
3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338
}


/**********************************************************************
  turboBM_matches()
  Search for pattern in text, returns true/false for match/no match
**********************************************************************/

bool Item_func_like::turboBM_matches(const char* text, int text_len) const
{
  register int bcShift;
  register int turboShift;
  int shift = pattern_len;
  int j     = 0;
  int u     = 0;
3339
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
3340

3341 3342
  const int plm1=  pattern_len - 1;
  const int tlmpl= text_len - pattern_len;
3343 3344

  /* Searching */
unknown's avatar
unknown committed
3345
  if (!cs->sort_order)
3346 3347 3348
  {
    while (j <= tlmpl)
    {
3349
      register int i= plm1;
3350 3351 3352 3353
      while (i >= 0 && pattern[i] == text[i + j])
      {
	i--;
	if (i == plm1 - shift)
3354
	  i-= u;
3355 3356
      }
      if (i < 0)
unknown's avatar
unknown committed
3357
	return 1;
3358 3359 3360

      register const int v = plm1 - i;
      turboShift = u - v;
3361
      bcShift    = bmBc[(uint) (uchar) text[i + j]] - plm1 + i;
3362 3363 3364 3365 3366 3367 3368 3369 3370 3371
      shift      = max(turboShift, bcShift);
      shift      = max(shift, bmGs[i]);
      if (shift == bmGs[i])
	u = min(pattern_len - shift, v);
      else
      {
	if (turboShift < bcShift)
	  shift = max(shift, u + 1);
	u = 0;
      }
3372
      j+= shift;
3373
    }
unknown's avatar
unknown committed
3374
    return 0;
3375 3376 3377 3378 3379 3380
  }
  else
  {
    while (j <= tlmpl)
    {
      register int i = plm1;
unknown's avatar
unknown committed
3381
      while (i >= 0 && likeconv(cs,pattern[i]) == likeconv(cs,text[i + j]))
3382 3383 3384
      {
	i--;
	if (i == plm1 - shift)
3385
	  i-= u;
3386 3387
      }
      if (i < 0)
unknown's avatar
unknown committed
3388
	return 1;
3389 3390 3391

      register const int v = plm1 - i;
      turboShift = u - v;
unknown's avatar
unknown committed
3392
      bcShift    = bmBc[(uint) likeconv(cs, text[i + j])] - plm1 + i;
3393 3394 3395 3396 3397 3398 3399 3400 3401 3402
      shift      = max(turboShift, bcShift);
      shift      = max(shift, bmGs[i]);
      if (shift == bmGs[i])
	u = min(pattern_len - shift, v);
      else
      {
	if (turboShift < bcShift)
	  shift = max(shift, u + 1);
	u = 0;
      }
3403
      j+= shift;
3404
    }
unknown's avatar
unknown committed
3405
    return 0;
3406 3407
  }
}
unknown's avatar
unknown committed
3408

3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429

/*
  Make a logical XOR of the arguments.

  SYNOPSIS
    val_int()

  DESCRIPTION
  If either operator is NULL, return NULL.

  NOTE
    As we don't do any index optimization on XOR this is not going to be
    very fast to use.

  TODO (low priority)
    Change this to be optimized as:
      A XOR B   ->  (A) == 1 AND (B) <> 1) OR (A <> 1 AND (B) == 1)
    To be able to do this, we would however first have to extend the MySQL
    range optimizer to handle OR better.
*/

unknown's avatar
unknown committed
3430 3431
longlong Item_cond_xor::val_int()
{
3432
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
3433 3434 3435
  List_iterator<Item> li(list);
  Item *item;
  int result=0;	
3436
  null_value=0;
unknown's avatar
unknown committed
3437 3438
  while ((item=li++))
  {
3439 3440 3441 3442 3443 3444
    result^= (item->val_int() != 0);
    if (item->null_value)
    {
      null_value=1;
      return 0;
    }
unknown's avatar
unknown committed
3445
  }
3446
  return (longlong) result;
unknown's avatar
unknown committed
3447
}
3448 3449 3450 3451

/*
  Apply NOT transformation to the item and return a new one.

unknown's avatar
unknown committed
3452
  SYNOPSIS
3453
    neg_transformer()
3454
    thd		thread handler
3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474

  DESCRIPTION
    Transform the item using next rules:
       a AND b AND ...    -> NOT(a) OR NOT(b) OR ...
       a OR b OR ...      -> NOT(a) AND NOT(b) AND ...
       NOT(a)             -> a
       a = b              -> a != b
       a != b             -> a = b
       a < b              -> a >= b
       a >= b             -> a < b
       a > b              -> a <= b
       a <= b             -> a > b
       IS NULL(a)         -> IS NOT NULL(a)
       IS NOT NULL(a)     -> IS NULL(a)

  RETURN
    New item or
    NULL if we cannot apply NOT transformation (see Item::neg_transformer()).
*/

3475
Item *Item_func_not::neg_transformer(THD *thd)	/* NOT(x)  ->  x */
3476
{
unknown's avatar
unknown committed
3477
  return args[0];
3478 3479
}

3480 3481

Item *Item_bool_rowready_func2::neg_transformer(THD *thd)
3482
{
3483 3484
  Item *item= negated_item();
  return item;
3485 3486
}

3487 3488 3489

/* a IS NULL  ->  a IS NOT NULL */
Item *Item_func_isnull::neg_transformer(THD *thd)
3490
{
3491 3492
  Item *item= new Item_func_isnotnull(args[0]);
  return item;
3493 3494
}

3495 3496 3497

/* a IS NOT NULL  ->  a IS NULL */
Item *Item_func_isnotnull::neg_transformer(THD *thd)
3498
{
3499 3500
  Item *item= new Item_func_isnull(args[0]);
  return item;
3501 3502
}

3503 3504 3505

Item *Item_cond_and::neg_transformer(THD *thd)	/* NOT(a AND b AND ...)  -> */
					/* NOT a OR NOT b OR ... */
3506
{
3507 3508 3509
  neg_arguments(thd);
  Item *item= new Item_cond_or(list);
  return item;
3510 3511
}

3512 3513 3514

Item *Item_cond_or::neg_transformer(THD *thd)	/* NOT(a OR b OR ...)  -> */
					/* NOT a AND NOT b AND ... */
3515
{
3516 3517 3518
  neg_arguments(thd);
  Item *item= new Item_cond_and(list);
  return item;
3519 3520
}

3521 3522

Item *Item_func_eq::negated_item()		/* a = b  ->  a != b */
3523
{
3524
  return new Item_func_ne(args[0], args[1]);
3525 3526
}

3527 3528

Item *Item_func_ne::negated_item()		/* a != b  ->  a = b */
3529
{
3530
  return new Item_func_eq(args[0], args[1]);
3531 3532
}

3533 3534

Item *Item_func_lt::negated_item()		/* a < b  ->  a >= b */
3535
{
3536
  return new Item_func_ge(args[0], args[1]);
3537 3538
}

3539 3540

Item *Item_func_ge::negated_item()		/* a >= b  ->  a < b */
3541
{
3542
  return new Item_func_lt(args[0], args[1]);
3543 3544
}

3545 3546

Item *Item_func_gt::negated_item()		/* a > b  ->  a <= b */
3547
{
3548
  return new Item_func_le(args[0], args[1]);
3549 3550
}

3551 3552

Item *Item_func_le::negated_item()		/* a <= b  ->  a > b */
3553
{
3554
  return new Item_func_gt(args[0], args[1]);
3555 3556
}

3557 3558
// just fake method, should never be called
Item *Item_bool_rowready_func2::negated_item()
3559
{
3560 3561
  DBUG_ASSERT(0);
  return 0;
3562
}
3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579

Item_equal::Item_equal(Item_field *f1, Item_field *f2)
  : Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  fields.push_back(f1);
  fields.push_back(f2);
}

Item_equal::Item_equal(Item *c, Item_field *f)
  : Item_bool_func(), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  fields.push_back(f);
  const_item= c;
}

3580

3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605
Item_equal::Item_equal(Item_equal *item_equal)
  : Item_bool_func(), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  List_iterator_fast<Item_field> li(item_equal->fields);
  Item_field *item;
  while ((item= li++))
  {
    fields.push_back(item);
  }
  const_item= item_equal->const_item;
  cond_false= item_equal->cond_false;
}

void Item_equal::add(Item *c)
{
  if (cond_false)
    return;
  if (!const_item)
  {
    const_item= c;
    return;
  }
  Item_func_eq *func= new Item_func_eq(c, const_item);
  func->set_cmp_func();
unknown's avatar
unknown committed
3606
  func->quick_fix_field();
3607 3608 3609 3610 3611 3612 3613 3614
  cond_false =  !(func->val_int());
}

void Item_equal::add(Item_field *f)
{
  fields.push_back(f);
}

unknown's avatar
unknown committed
3615 3616
uint Item_equal::members()
{
3617
  return fields.elements;
unknown's avatar
unknown committed
3618 3619 3620 3621 3622 3623 3624 3625
}


/*
  Check whether a field is referred in the multiple equality 

  SYNOPSIS
    contains()
unknown's avatar
unknown committed
3626
    field   field whose occurrence is to be checked
unknown's avatar
unknown committed
3627 3628
  
  DESCRIPTION
unknown's avatar
unknown committed
3629
    The function checks whether field is occurred in the Item_equal object 
unknown's avatar
unknown committed
3630 3631 3632 3633 3634 3635
    
  RETURN VALUES
    1       if nultiple equality contains a reference to field
    0       otherwise    
*/

3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647
bool Item_equal::contains(Field *field)
{
  List_iterator_fast<Item_field> it(fields);
  Item_field *item;
  while ((item= it++))
  {
    if (field->eq(item->field))
        return 1;
  }
  return 0;
}

unknown's avatar
unknown committed
3648 3649 3650 3651 3652 3653 3654 3655 3656

/*
  Join members of another Item_equal object  

  SYNOPSIS
    merge()
    item    multiple equality whose members are to be joined
  
  DESCRIPTION
unknown's avatar
unknown committed
3657
    The function actually merges two multiple equalities.
unknown's avatar
unknown committed
3658 3659 3660 3661 3662 3663 3664 3665 3666
    After this operation the Item_equal object additionally contains
    the field items of another item of the type Item_equal.
    If the optional constant items are not equal the cond_false flag is
    set to 1.  
       
  RETURN VALUES
    none    
*/

3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677
void Item_equal::merge(Item_equal *item)
{
  fields.concat(&item->fields);
  Item *c= item->const_item;
  if (c)
  {
    /* 
      The flag cond_false will be set to 1 after this, if 
      the multiple equality already contains a constant and its 
      value is  not equal to the value of c.
    */
unknown's avatar
unknown committed
3678
    add(c);
3679 3680 3681 3682
  }
  cond_false|= item->cond_false;
} 

unknown's avatar
unknown committed
3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708

/*
  Order field items in multiple equality according to a sorting criteria 

  SYNOPSIS
    sort()
    cmp          function to compare field item 
    arg          context extra parameter for the cmp function
  
  DESCRIPTION
    The function perform ordering of the field items in the Item_equal
    object according to the criteria determined by the cmp callback parameter.
    If cmp(item_field1,item_field2,arg)<0 than item_field1 must be
    placed after item_fiel2.

  IMPLEMENTATION
    The function sorts field items by the exchange sort algorithm.
    The list of field items is looked through and whenever two neighboring
    members follow in a wrong order they are swapped. This is performed
    again and again until we get all members in a right order.
         
  RETURN VALUES
    None    
*/

void Item_equal::sort(Item_field_cmpfunc cmp, void *arg)
3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720
{
  bool swap;
  List_iterator<Item_field> it(fields);
  do
  {
    Item_field *item1= it++;
    Item_field **ref1= it.ref();
    Item_field *item2;

    swap= FALSE;
    while ((item2= it++))
    {
unknown's avatar
unknown committed
3721 3722
      Item_field **ref2= it.ref();
      if (cmp(item1, item2, arg) < 0)
3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738
      {
        Item_field *item= *ref1;
        *ref1= *ref2;
        *ref2= item;
        swap= TRUE;
      }
      else
      {
        item1= item2;
        ref1= ref2;
      }
    }
    it.rewind();
  } while (swap);
}

3739
bool Item_equal::fix_fields(THD *thd, Item **ref)
3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763
{
  List_iterator_fast<Item_field> li(fields);
  Item *item;
  not_null_tables_cache= used_tables_cache= 0;
  const_item_cache= 0;
  while ((item=li++))
  {
    table_map tmp_table_map;
    used_tables_cache|= item->used_tables();
    tmp_table_map= item->not_null_tables();
    not_null_tables_cache|= tmp_table_map;
    if (item->maybe_null)
      maybe_null=1;
  }
  fix_length_and_dec();
  fixed= 1;
  return 0;
}

void Item_equal::update_used_tables()
{
  List_iterator_fast<Item_field> li(fields);
  Item *item;
  not_null_tables_cache= used_tables_cache= 0;
unknown's avatar
unknown committed
3764 3765
  if ((const_item_cache= cond_false))
    return;
3766 3767 3768 3769 3770 3771 3772 3773 3774 3775
  while ((item=li++))
  {
    item->update_used_tables();
    used_tables_cache|= item->used_tables();
    const_item_cache&= item->const_item();
  }
}

longlong Item_equal::val_int()
{
3776
  Item_field *item_field;
3777 3778 3779 3780 3781 3782 3783
  if (cond_false)
    return 0;
  List_iterator_fast<Item_field> it(fields);
  Item *item= const_item ? const_item : it++;
  if ((null_value= item->null_value))
    return 0;
  eval_item->store_value(item);
3784
  while ((item_field= it++))
3785
  {
3786 3787 3788 3789 3790 3791
    /* Skip fields of non-const tables. They haven't been read yet */
    if (item_field->field->table->const_table)
    {
      if ((null_value= item_field->null_value) || eval_item->cmp(item_field))
        return 0;
    }
3792 3793 3794 3795 3796 3797 3798
  }
  return 1;
}

void Item_equal::fix_length_and_dec()
{
  Item *item= const_item ? const_item : get_first();
unknown's avatar
unknown committed
3799 3800
  eval_item= cmp_item::get_comparator(item->result_type(),
                                      item->collation.collation);
3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814
  if (item->result_type() == STRING_RESULT)
    eval_item->cmp_charset= cmp_collation.collation;
}

bool Item_equal::walk(Item_processor processor, byte *arg)
{
  List_iterator_fast<Item_field> it(fields);
  Item *item;
  while ((item= it++))
    if (item->walk(processor, arg))
      return 1;
  return Item_func::walk(processor, arg);
}

unknown's avatar
unknown committed
3815
Item *Item_equal::transform(Item_transformer transformer, byte *arg)
3816 3817 3818 3819 3820
{
  List_iterator<Item_field> it(fields);
  Item *item;
  while ((item= it++))
  {
unknown's avatar
unknown committed
3821
    Item *new_item= item->transform(transformer, arg);
3822 3823 3824 3825 3826
    if (!new_item)
      return 0;
    if (new_item != item)
      it.replace((Item_field *) new_item);
  }
unknown's avatar
unknown committed
3827
  return Item_func::transform(transformer, arg);
3828 3829 3830 3831 3832 3833 3834 3835
}

void Item_equal::print(String *str)
{
  str->append(func_name());
  str->append('(');
  List_iterator_fast<Item_field> it(fields);
  Item *item;
unknown's avatar
unknown committed
3836 3837 3838 3839 3840
  if (const_item)
    const_item->print(str);
  else
  {
    item= it++;
3841
    item->print(str);
unknown's avatar
unknown committed
3842
  }
3843 3844 3845 3846 3847 3848 3849 3850 3851
  while ((item= it++))
  {
    str->append(',');
    str->append(' ');
    item->print(str);
  }
  str->append(')');
}