fix for bug #1790:

"BIT_AND() result in GROUP BY different when SQL_BIG_RESULT used"

return value of BIT_AND changed to BIGINT SIGNED
Also the patch fixes another bug: when temporary table is in use and one of
values in group is NULL, BIT_AND always returns zero.
Fixed it to always skip null values.


mysql-test/r/func_group.result:
  bug #1790: test results fixed
sql/item_sum.cc:
  fix for bug #1790:
  update_field() rewritten to use add() and thus was moved
  to Item_sum_bit::update_field()
  Item_sum_bit::reset_field() was rewritten to take into account
  reset_bits.
sql/item_sum.h:
  fix for bug #1790:
  Item_sum::update_field() and Item_sum::reset_field() commented
  Item_sum_and changed to return BIGINT SIGNED
  Item_sum_and::update_field() and Item_sum_or::update_field)
  were replaced with generic Item_sum_bit::update_field()

mysql-test/r/func_group.result

@@ -47,7 +47,7 @@ sum(all a)	count(all a)	avg(all a)	std(all a)	bit_or(all a)	bit_and(all a)	min(a
 21	6	3.5000	1.7078	7	0	1	6		E
 select grp, sum(a),count(a),avg(a),std(a),bit_or(a),bit_and(a),min(a),max(a),min(c),max(c) from t1 group by grp;
 grp	sum(a)	count(a)	avg(a)	std(a)	bit_or(a)	bit_and(a)	min(a)	max(a)	min(c)	max(c)
-NULL	NULL	0	NULL	NULL	0	0	NULL	NULL		
+NULL	NULL	0	NULL	NULL	0	-1	NULL	NULL		
 1	1	1	1.0000	0.0000	1	1	1	1	a	a
 2	5	2	2.5000	0.5000	3	2	2	3	b	c
 3	15	3	5.0000	0.8165	7	4	4	6	C	E
@@ -218,8 +218,8 @@ insert into t1 values (1,null);
 insert into t1 values (2,null);
 select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
-1	0	NULL	NULL	NULL	NULL	NULL	0	0
-2	0	NULL	NULL	NULL	NULL	NULL	0	0
+1	0	NULL	NULL	NULL	NULL	NULL	-1	0
+2	0	NULL	NULL	NULL	NULL	NULL	-1	0
 select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
 1	0	NULL	NULL	NULL	NULL	NULL	-1	0
@@ -227,8 +227,8 @@ a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
 insert into t1 values (2,1);
 select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
-1	0	NULL	NULL	NULL	NULL	NULL	0	0
-2	1	1	1.0000	0.0000	1	1	0	1
+1	0	NULL	NULL	NULL	NULL	NULL	-1	0
+2	1	1	1.0000	0.0000	1	1	1	1
 select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
 1	0	NULL	NULL	NULL	NULL	NULL	-1	0
@@ -236,8 +236,8 @@ a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
 insert into t1 values (3,1);
 select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)
-1	0	NULL	NULL	NULL	NULL	NULL	0	0
-2	1	1	1.0000	0.0000	1	1	0	1
+1	0	NULL	NULL	NULL	NULL	NULL	-1	0
+2	1	1	1.0000	0.0000	1	1	1	1
 3	1	1	1.0000	0.0000	1	1	1	1
 select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
 a	count(b)	sum(b)	avg(b)	std(b)	min(b)	max(b)	bit_and(b)	bit_or(b)

sql/item_sum.cc

@@ -614,10 +614,19 @@ void Item_sum_avg::reset_field()
 }
 
 void Item_sum_bit::reset_field()
+{
+  char *res= result_field->ptr;
+  bits= reset_bits;
+  add();
+  int8store(res, bits);
+}
+
+void Item_sum_bit::update_field()
 {
   char *res=result_field->ptr;
-  ulonglong nr=(ulonglong) args[0]->val_int();
-  int8store(res,nr);
+  bits= uint8korr(res);
+  add();
+  int8store(res, bits);
 }
 
 /*
@@ -756,28 +765,6 @@ Item_sum_hybrid::min_max_update_int_field()
 }
 
 
-void Item_sum_or::update_field()
-{
-  ulonglong nr;
-  char *res=result_field->ptr;
-
-  nr=uint8korr(res);
-  nr|= (ulonglong) args[0]->val_int();
-  int8store(res,nr);
-}
-
-
-void Item_sum_and::update_field()
-{
-  ulonglong nr;
-  char *res=result_field->ptr;
-
-  nr=uint8korr(res);
-  nr&= (ulonglong) args[0]->val_int();
-  int8store(res,nr);
-}
-
-
 Item_avg_field::Item_avg_field(Item_sum_avg *item)
 {
   name=item->name;
@@ -787,6 +774,7 @@ Item_avg_field::Item_avg_field(Item_sum_avg *item)
   maybe_null=1;
 }
 
+
 double Item_avg_field::val()
 {
   double nr;

sql/item_sum.h

@@ -55,7 +55,18 @@ public:
   virtual enum Sumfunctype sum_func () const=0;
   virtual void reset()=0;
   virtual bool add()=0;
+  /*
+    Called when new group is started and results are being saved in
+    a temporary table. Similar to reset(), but must also store value in
+    result_field. Like reset() it is supposed to reset start value to
+    default.
+  */
   virtual void reset_field()=0;
+  /*
+    Called for each new value in the group, when temporary table is in use.
+    Similar to add(), but uses temporary table field to obtain current value,
+    Updated value is then saved in the field.
+  */
   virtual void update_field()=0;
   virtual bool keep_field_type(void) const { return 0; }
   virtual void fix_length_and_dec() { maybe_null=1; null_value=1; }
@@ -360,20 +371,20 @@ class Item_sum_bit :public Item_sum_int
   void reset();
   longlong val_int();
   void reset_field();
+  void update_field();
   unsigned int size_of() { return sizeof(*this);}  
-  void fix_length_and_dec()
-  { decimals=0; max_length=21; unsigned_flag=1; maybe_null=null_value=0; }
 };
 
 
 class Item_sum_or :public Item_sum_bit
 {
-  public:
+public:
   Item_sum_or(Item *item_par) :Item_sum_bit(item_par,LL(0)) {}
   bool add();
-  void update_field();
   const char *func_name() const { return "bit_or"; }
   unsigned int size_of() { return sizeof(*this);}  
+  void fix_length_and_dec()
+  { decimals=0; max_length=21; unsigned_flag=1; maybe_null=null_value=0; }
 };
 
 
@@ -382,9 +393,10 @@ class Item_sum_and :public Item_sum_bit
   public:
   Item_sum_and(Item *item_par) :Item_sum_bit(item_par, ~(ulonglong) LL(0)) {}
   bool add();
-  void update_field();
   const char *func_name() const { return "bit_and"; }
   unsigned int size_of() { return sizeof(*this);}  
+  void fix_length_and_dec()
+  { decimals=0; max_length=21; unsigned_flag=0; maybe_null=null_value=0; }
 };
 
 /*