Bug#22687 (Functions UNIQUE_USERS, GROUP_UNIQUE_USERS)

According to some internal communication, these two functions are place
holders for future enhancements. Because they use a variable number of
parameters, the implementation defined a reserved keyword for them in the
parser grammar.

Unfortunately, doing so creates a bug similar to Bug 21114 reported for the
function FORMAT.

In the 5.1 code base, due to improvements in the code implemented with bug
21114, having a reserved keyword for functions with a variable number of
arguments is not needed any more by the implementation.

As a result, this fix removes the place-holder implementation, and removes
the unnecessary reserved keywords. Should the functions UNIQUE_USERS and
GROUP_UNIQUE_USERS be finally implemented in a later release, the
implementation should sub class Create_native_func in sql/item_create.cc.
For example, see the class Create_func_concat.

libmysqld/Makefile.am

@@ -51,7 +51,7 @@ sqlsources = derror.cc field.cc field_conv.cc strfunc.cc filesort.cc \
 	hostname.cc init.cc password.c \
 	item.cc item_buff.cc item_cmpfunc.cc item_create.cc \
 	item_func.cc item_strfunc.cc item_sum.cc item_timefunc.cc \
-	item_geofunc.cc item_uniq.cc item_subselect.cc item_row.cc\
+	item_geofunc.cc item_subselect.cc item_row.cc\
 	item_xmlfunc.cc \
 	key.cc lock.cc log.cc log_event.cc sql_state.c \
 	protocol.cc net_serv.cc opt_range.cc \

mysql-test/r/parser.result

@@ -49,7 +49,7 @@ ERROR 42000: You have an error in your SQL syntax; check the manual that corresp
 create table GROUP_CONCAT (a int);
 drop table GROUP_CONCAT;
 create table GROUP_UNIQUE_USERS(a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'GROUP_UNIQUE_USERS(a int)' at line 1
+drop table GROUP_UNIQUE_USERS;
 create table GROUP_UNIQUE_USERS (a int);
 drop table GROUP_UNIQUE_USERS;
 create table MAX(a int);
@@ -121,7 +121,7 @@ ERROR 42000: You have an error in your SQL syntax; check the manual that corresp
 create table TRIM (a int);
 drop table TRIM;
 create table UNIQUE_USERS(a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNIQUE_USERS(a int)' at line 1
+drop table UNIQUE_USERS;
 create table UNIQUE_USERS (a int);
 drop table UNIQUE_USERS;
 create table VARIANCE(a int);
@@ -186,9 +186,9 @@ ERROR 42000: You have an error in your SQL syntax; check the manual that corresp
 create table GROUP_CONCAT (a int);
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'GROUP_CONCAT (a int)' at line 1
 create table GROUP_UNIQUE_USERS(a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'GROUP_UNIQUE_USERS(a int)' at line 1
+drop table GROUP_UNIQUE_USERS;
 create table GROUP_UNIQUE_USERS (a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'GROUP_UNIQUE_USERS (a int)' at line 1
+drop table GROUP_UNIQUE_USERS;
 create table MAX(a int);
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'MAX(a int)' at line 1
 create table MAX (a int);
@@ -258,9 +258,9 @@ ERROR 42000: You have an error in your SQL syntax; check the manual that corresp
 create table TRIM (a int);
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'TRIM (a int)' at line 1
 create table UNIQUE_USERS(a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNIQUE_USERS(a int)' at line 1
+drop table UNIQUE_USERS;
 create table UNIQUE_USERS (a int);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNIQUE_USERS (a int)' at line 1
+drop table UNIQUE_USERS;
 create table VARIANCE(a int);
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'VARIANCE(a int)' at line 1
 create table VARIANCE (a int);

mysql-test/t/parser.test

@@ -77,8 +77,9 @@ create table GROUP_CONCAT(a int);
 create table GROUP_CONCAT (a int);
 drop table GROUP_CONCAT;
 
---error ER_PARSE_ERROR
+# Limitation removed in 5.1
 create table GROUP_UNIQUE_USERS(a int);
+drop table GROUP_UNIQUE_USERS;
 create table GROUP_UNIQUE_USERS (a int);
 drop table GROUP_UNIQUE_USERS;
 
@@ -167,8 +168,9 @@ create table TRIM(a int);
 create table TRIM (a int);
 drop table TRIM;
 
---error ER_PARSE_ERROR
+# Limitation removed in 5.1
 create table UNIQUE_USERS(a int);
+drop table UNIQUE_USERS;
 create table UNIQUE_USERS (a int);
 drop table UNIQUE_USERS;
 
@@ -249,10 +251,11 @@ create table GROUP_CONCAT(a int);
 --error ER_PARSE_ERROR
 create table GROUP_CONCAT (a int);
 
---error ER_PARSE_ERROR
+# Limitation removed in 5.1
 create table GROUP_UNIQUE_USERS(a int);
---error ER_PARSE_ERROR
+drop table GROUP_UNIQUE_USERS;
 create table GROUP_UNIQUE_USERS (a int);
+drop table GROUP_UNIQUE_USERS;
 
 --error ER_PARSE_ERROR
 create table MAX(a int);
@@ -339,10 +342,11 @@ create table TRIM(a int);
 --error ER_PARSE_ERROR
 create table TRIM (a int);
 
---error ER_PARSE_ERROR
+# Limitation removed in 5.1
 create table UNIQUE_USERS(a int);
---error ER_PARSE_ERROR
+drop table UNIQUE_USERS;
 create table UNIQUE_USERS (a int);
+drop table UNIQUE_USERS;
 
 --error ER_PARSE_ERROR
 create table VARIANCE(a int);

sql/Makefile.am

@@ -43,7 +43,7 @@ mysqld_LDADD =		@MYSQLD_EXTRA_LDFLAGS@ \
 			$(LDADD)  $(CXXLDFLAGS) $(WRAPLIBS) @LIBDL@ \
                         @yassl_libs@ @openssl_libs@
 noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
-			item_strfunc.h item_timefunc.h item_uniq.h \
+			item_strfunc.h item_timefunc.h \
 			item_xmlfunc.h \
 			item_create.h item_subselect.h item_row.h \
 			mysql_priv.h item_geofunc.h sql_bitmap.h \
@@ -83,7 +83,7 @@ mysqld_SOURCES =	sql_lex.cc sql_handler.cc sql_partition.cc \
 			sql_base.cc table.cc sql_select.cc sql_insert.cc \
 			sql_prepare.cc sql_error.cc sql_locale.cc \
 			sql_update.cc sql_delete.cc uniques.cc sql_do.cc \
-			procedure.cc item_uniq.cc sql_test.cc \
+			procedure.cc sql_test.cc \
 			log.cc log_event.cc init.cc derror.cc sql_acl.cc \
 			unireg.cc des_key_file.cc \
 			discover.cc time.cc opt_range.cc opt_sum.cc \

sql/item.h

@@ -2135,7 +2135,6 @@ public:
 #include "item_strfunc.h"
 #include "item_geofunc.h"
 #include "item_timefunc.h"
-#include "item_uniq.h"
 #include "item_subselect.h"
 #include "item_xmlfunc.h"
 #endif

sql/item_sum.h

@@ -223,7 +223,7 @@ class Item_sum :public Item_result_field
 public:
   enum Sumfunctype
   { COUNT_FUNC, COUNT_DISTINCT_FUNC, SUM_FUNC, SUM_DISTINCT_FUNC, AVG_FUNC,
-    AVG_DISTINCT_FUNC, MIN_FUNC, MAX_FUNC, UNIQUE_USERS_FUNC, STD_FUNC,
+    AVG_DISTINCT_FUNC, MIN_FUNC, MAX_FUNC, STD_FUNC,
     VARIANCE_FUNC, SUM_BIT_FUNC, UDF_SUM_FUNC, GROUP_CONCAT_FUNC
   };
 

sql/item_uniq.cc

-/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
-
-   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.
-
-   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.
-
-   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 */
-
-/* Compability file */
-
-#ifdef USE_PRAGMA_IMPLEMENTATION
-#pragma implementation				// gcc: Class implementation
-#endif
-
-#include "mysql_priv.h"
-
-Field *Item_sum_unique_users::create_tmp_field(bool group, TABLE *table,
-                                               uint convert_blob_length)
-{
-  Field *field= new Field_long(9, maybe_null, name, 1);
-  if (field)
-    field->init(table);
-  return field;
-}

sql/item_uniq.h

-/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
-
-   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.
-
-   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.
-
-   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 */
-
-/* Compability file ; This file only contains dummy functions */
-
-#ifdef USE_PRAGMA_INTERFACE
-#pragma interface
-#endif
-
-#include <queues.h>
-
-class Item_func_unique_users :public Item_real_func
-{
-public:
-  Item_func_unique_users(Item *name_arg,int start,int end,List<Item> &list)
-    :Item_real_func(list) {}
-  double val_real() { DBUG_ASSERT(fixed == 1); return 0.0; }
-  void fix_length_and_dec() { decimals=0; max_length=6; }
-  void print(String *str) { str->append(STRING_WITH_LEN("0.0")); }
-  const char *func_name() const { return "unique_users"; }
-};
-
-
-class Item_sum_unique_users :public Item_sum_num
-{
-public:
-  Item_sum_unique_users(Item *name_arg,int start,int end,Item *item_arg)
-    :Item_sum_num(item_arg) {}
-  Item_sum_unique_users(THD *thd, Item_sum_unique_users *item)
-    :Item_sum_num(thd, item) {}
-  double val_real() { DBUG_ASSERT(fixed == 1); return 0.0; }
-  enum Sumfunctype sum_func () const {return UNIQUE_USERS_FUNC;}
-  void clear() {}
-  bool add() { return 0; }
-  void reset_field() {}
-  void update_field() {}
-  bool fix_fields(THD *thd, Item **ref)
-  {
-    DBUG_ASSERT(fixed == 0);
-    fixed= 1;
-    return FALSE;
-  }
-  Item *copy_or_same(THD* thd)
-  {
-    return new Item_sum_unique_users(thd, this);
-  }
-  void print(String *str) { str->append(STRING_WITH_LEN("0.0")); }
-  Field *create_tmp_field(bool group, TABLE *table, uint convert_blob_length);
-  const char *func_name() const { return "sum_unique_users"; }
-};

sql/lex.h

@@ -593,7 +593,6 @@ static SYMBOL sql_functions[] = {
   { "DATE_SUB",		SYM(DATE_SUB_INTERVAL)},
   { "EXTRACT",		SYM(EXTRACT_SYM)},
   { "GROUP_CONCAT",	SYM(GROUP_CONCAT_SYM)},
-  { "GROUP_UNIQUE_USERS",	SYM(GROUP_UNIQUE_USERS)},
   { "MAX",		SYM(MAX_SYM)},
   { "MID",		SYM(SUBSTRING)},	/* unireg function */
   { "MIN",		SYM(MIN_SYM)},
@@ -611,7 +610,6 @@ static SYMBOL sql_functions[] = {
   { "SYSDATE",		SYM(SYSDATE)},
   { "SYSTEM_USER",      SYM(USER)},
   { "TRIM",		SYM(TRIM)},
-  { "UNIQUE_USERS",	SYM(UNIQUE_USERS)},
   { "VARIANCE",		SYM(VARIANCE_SYM)},
   { "VAR_POP",		SYM(VARIANCE_SYM)},
   { "VAR_SAMP",		SYM(VAR_SAMP_SYM)},

sql/mysql_priv.h

@@ -36,6 +36,7 @@
 #include <signal.h>
 #include <thr_lock.h>
 #include <my_base.h>			/* Needed by field.h */
+#include <queues.h>
 #include "sql_bitmap.h"
 #include "sql_array.h"
 

sql/sql_yacc.yy

@@ -537,7 +537,6 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 %token  GRANTS
 %token  GROUP                         /* SQL-2003-R */
 %token  GROUP_CONCAT_SYM
-%token  GROUP_UNIQUE_USERS
 %token  GT_SYM                        /* OPERATOR */
 %token  HANDLER_SYM
 %token  HASH_SYM
@@ -864,7 +863,6 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 %token  UNINSTALL_SYM
 %token  UNION_SYM                     /* SQL-2003-R */
 %token  UNIQUE_SYM
-%token  UNIQUE_USERS
 %token  UNKNOWN_SYM                   /* SQL-2003-R */
 %token  UNLOCK_SYM
 %token  UNSIGNED
@@ -6279,10 +6277,6 @@ simple_expr:
             }
             $$= new (YYTHD->mem_root) Item_func_interval((Item_row *)$1);
           }
-	| UNIQUE_USERS '(' text_literal ',' NUM ',' NUM ',' expr_list ')'
-	  {
-            $$= new Item_func_unique_users($3,atoi($5.str),atoi($7.str), * $9);
-	  }
         ;
 
 /*
@@ -6769,8 +6763,6 @@ sum_expr:
 	  { Select->in_sum_expr--; }
 	  ')'
 	  { $$=new Item_sum_count_distinct(* $5); }
-	| GROUP_UNIQUE_USERS '(' text_literal ',' NUM ',' NUM ',' in_sum_expr ')'
-	  { $$= new Item_sum_unique_users($3,atoi($5.str),atoi($7.str),$9); }
 	| MIN_SYM '(' in_sum_expr ')'
 	  { $$=new Item_sum_min($3); }
 /*