From 04f5c46d5dd9911811bce2683b90e2acc711f94e Mon Sep 17 00:00:00 2001 From: "evgen@moonbone.local" <> Date: Sat, 10 Mar 2007 00:29:02 +0300 Subject: [PATCH 1/3] Bug#22331: Wrong WHERE in EXPLAIN EXTENDED when all expressions were optimized away. Additional fix for bug#22331. Now Item_field prints its value in the case of the const field. --- mysql-test/r/explain.result | 6 +++--- mysql-test/r/func_default.result | 2 +- mysql-test/r/func_regexp.result | 2 +- mysql-test/r/func_str.result | 6 +++--- mysql-test/r/func_test.result | 2 +- mysql-test/r/having.result | 2 +- mysql-test/r/subselect.result | 22 +++++++++++----------- mysql-test/r/union.result | 2 +- mysql-test/r/varbinary.result | 2 +- sql/item.cc | 21 +++++++++++++++++++-- sql/item.h | 1 + sql/sql_union.cc | 6 ++++++ 12 files changed, 49 insertions(+), 25 deletions(-) diff --git a/mysql-test/r/explain.result b/mysql-test/r/explain.result index e0afaaef201..24ff44945bf 100644 --- a/mysql-test/r/explain.result +++ b/mysql-test/r/explain.result @@ -64,7 +64,7 @@ explain extended select * from v1 where f2=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select `test`.`t1`.`f1` AS `f1`,`test`.`t1`.`f2` AS `f2` from `test`.`t1` where 1 +Note 1003 select '1' AS `f1`,'1' AS `f2` from `test`.`t1` where 1 explain extended select * from t1 where 0; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE @@ -74,7 +74,7 @@ explain extended select * from t1 where 1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select `test`.`t1`.`f1` AS `f1`,`test`.`t1`.`f2` AS `f2` from `test`.`t1` where 1 +Note 1003 select '1' AS `f1`,'1' AS `f2` from `test`.`t1` where 1 explain extended select * from t1 having 0; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible HAVING @@ -84,6 +84,6 @@ explain extended select * from t1 having 1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select `test`.`t1`.`f1` AS `f1`,`test`.`t1`.`f2` AS `f2` from `test`.`t1` having 1 +Note 1003 select '1' AS `f1`,'1' AS `f2` from `test`.`t1` having 1 drop view v1; drop table t1; diff --git a/mysql-test/r/func_default.result b/mysql-test/r/func_default.result index 5742ddd102b..84ead3b73c7 100644 --- a/mysql-test/r/func_default.result +++ b/mysql-test/r/func_default.result @@ -8,7 +8,7 @@ explain extended select default(str), default(strnull), default(intg), default(r id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select default(`test`.`t1`.`str`) AS `default(str)`,default(`test`.`t1`.`strnull`) AS `default(strnull)`,default(`test`.`t1`.`intg`) AS `default(intg)`,default(`test`.`t1`.`rel`) AS `default(rel)` from `test`.`t1` +Note 1003 select default('') AS `default(str)`,default('') AS `default(strnull)`,default('0') AS `default(intg)`,default('0') AS `default(rel)` from `test`.`t1` select * from t1 where str <> default(str); str strnull intg rel 0 0 diff --git a/mysql-test/r/func_regexp.result b/mysql-test/r/func_regexp.result index 787463c6aa3..584c8a9b820 100644 --- a/mysql-test/r/func_regexp.result +++ b/mysql-test/r/func_regexp.result @@ -40,7 +40,7 @@ explain extended select * from t1 where xxx regexp('is a test of some long text id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select `test`.`t1`.`xxx` AS `xxx` from `test`.`t1` where (`test`.`t1`.`xxx` regexp _latin1'is a test of some long text to') +Note 1003 select 'this is a test of some long text to see what happens' AS `xxx` from `test`.`t1` where ('this is a test of some long text to see what happens' regexp _latin1'is a test of some long text to') select * from t1 where xxx regexp('is a test of some long text to '); xxx this is a test of some long text to see what happens diff --git a/mysql-test/r/func_str.result b/mysql-test/r/func_str.result index d09d3aeb529..02f883d8b43 100644 --- a/mysql-test/r/func_str.result +++ b/mysql-test/r/func_str.result @@ -1089,12 +1089,12 @@ explain extended select encode(f1,'zxcv') as 'enc' from t1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select encode(`test`.`t1`.`f1`,'zxcv') AS `enc` from `test`.`t1` +Note 1003 select encode('','zxcv') AS `enc` from `test`.`t1` explain extended select decode(f1,'zxcv') as 'enc' from t1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select decode(`test`.`t1`.`f1`,'zxcv') AS `enc` from `test`.`t1` +Note 1003 select decode('','zxcv') AS `enc` from `test`.`t1` drop table t1; End of 4.1 tests create table t1 (d decimal default null); @@ -1158,7 +1158,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 const PRIMARY PRIMARY 12 const 1 Using index 1 SIMPLE t1 ref code code 13 const 3 Using where; Using index Warnings: -Note 1003 select `test`.`t1`.`code` AS `code`,`test`.`t2`.`id` AS `id` from `test`.`t1` join `test`.`t2` where ((`test`.`t1`.`code` = _latin1'a12') and (length(`test`.`t1`.`code`) = 5)) +Note 1003 select `test`.`t1`.`code` AS `code`,'a12' AS `id` from `test`.`t1` join `test`.`t2` where ((`test`.`t1`.`code` = _latin1'a12') and (length(`test`.`t1`.`code`) = 5)) DROP TABLE t1,t2; select locate('he','hello',-2); locate('he','hello',-2) diff --git a/mysql-test/r/func_test.result b/mysql-test/r/func_test.result index c3fbdb3b3bf..65293398155 100644 --- a/mysql-test/r/func_test.result +++ b/mysql-test/r/func_test.result @@ -87,7 +87,7 @@ explain extended select - a from t1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 select -(`test`.`t1`.`a`) AS `- a` from `test`.`t1` +Note 1003 select -('1') AS `- a` from `test`.`t1` drop table t1; select 5 between 0 and 10 between 0 and 1,(5 between 0 and 10) between 0 and 1; 5 between 0 and 10 between 0 and 1 (5 between 0 and 10) between 0 and 1 diff --git a/mysql-test/r/having.result b/mysql-test/r/having.result index 68b13b5fc0a..9b131109809 100644 --- a/mysql-test/r/having.result +++ b/mysql-test/r/having.result @@ -12,7 +12,7 @@ explain extended select count(a) as b from t1 where a=0 having b >=0; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: -Note 1003 select count(`test`.`t1`.`a`) AS `b` from `test`.`t1` where 0 having (`b` >= 0) +Note 1003 select count('0') AS `b` from `test`.`t1` where 0 having (`b` >= 0) drop table t1; CREATE TABLE t1 ( raw_id int(10) NOT NULL default '0', diff --git a/mysql-test/r/subselect.result b/mysql-test/r/subselect.result index 373d49c29d2..79d29a90b2b 100644 --- a/mysql-test/r/subselect.result +++ b/mysql-test/r/subselect.result @@ -50,7 +50,7 @@ id select_type table type possible_keys key key_len ref rows Extra Warnings: Note 1276 Field or reference 'a' of SELECT #3 was resolved in SELECT #1 Note 1276 Field or reference 'b.a' of SELECT #3 was resolved in SELECT #1 -Note 1003 select 1 AS `1` from (select 1 AS `a`) `b` having ((select `b`.`a` AS `a`) = 1) +Note 1003 select 1 AS `1` from (select 1 AS `a`) `b` having ((select '1' AS `a`) = 1) SELECT 1 FROM (SELECT 1 as a) as b HAVING (SELECT a)=1; 1 1 @@ -204,7 +204,7 @@ id select_type table type possible_keys key key_len ref rows Extra 3 DERIVED t2 ALL NULL NULL NULL NULL 2 Using where 2 SUBQUERY t3 ALL NULL NULL NULL NULL 3 Using where; Using filesort Warnings: -Note 1003 select (select `test`.`t3`.`a` AS `a` from `test`.`t3` where (`test`.`t3`.`a` < 8) order by 1 desc limit 1) AS `(select t3.a from t3 where a<8 order by 1 desc limit 1)`,`tt`.`a` AS `a` from (select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where (`test`.`t2`.`a` > 1)) `tt` +Note 1003 select (select `test`.`t3`.`a` AS `a` from `test`.`t3` where (`test`.`t3`.`a` < 8) order by 1 desc limit 1) AS `(select t3.a from t3 where a<8 order by 1 desc limit 1)`,'2' AS `a` from (select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where (`test`.`t2`.`a` > 1)) `tt` select * from t1 where t1.a=(select t2.a from t2 where t2.b=(select max(a) from t3) order by 1 desc limit 1); a 2 @@ -315,7 +315,7 @@ NULL UNION RESULT ALL NULL NULL NULL NULL NULL Warnings: Note 1276 Field or reference 'test.t2.a' of SELECT #2 was resolved in SELECT #1 Note 1276 Field or reference 'test.t2.a' of SELECT #3 was resolved in SELECT #1 -Note 1003 select (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` = `test`.`t2`.`a`) union select `test`.`t5`.`a` AS `a` from `test`.`t5` where (`test`.`t5`.`a` = `test`.`t2`.`a`)) AS `(select a from t1 where t1.a=t2.a union select a from t5 where t5.a=t2.a)`,`test`.`t2`.`a` AS `a` from `test`.`t2` +Note 1003 select (select '2' AS `a` from `test`.`t1` where ('2' = `test`.`t2`.`a`) union select `test`.`t5`.`a` AS `a` from `test`.`t5` where (`test`.`t5`.`a` = `test`.`t2`.`a`)) AS `(select a from t1 where t1.a=t2.a union select a from t5 where t5.a=t2.a)`,`test`.`t2`.`a` AS `a` from `test`.`t2` select (select a from t1 where t1.a=t2.a union all select a from t5 where t5.a=t2.a), a from t2; ERROR 21000: Subquery returns more than 1 row create table t6 (patient_uq int, clinic_uq int, index i1 (clinic_uq)); @@ -368,7 +368,7 @@ id select_type table type possible_keys key key_len ref rows Extra 2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 3 SUBQUERY t8 const PRIMARY PRIMARY 37 1 Using index Warnings: -Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` AS `email` from `test`.`t8` where 1) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where 1 +Note 1003 select 'joce' AS `pseudo`,(select 'test' AS `email` from `test`.`t8` where 1) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where 1 SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM t8 WHERE pseudo='joce'); ERROR 21000: Operand should contain 1 column(s) @@ -547,7 +547,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 Using index 2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away Warnings: -Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = _latin1'1')) +Note 1003 select '3' AS `numreponse` from `test`.`t1` where (('1' = _latin1'1')) drop table t1; CREATE TABLE t1 (a int(1)); INSERT INTO t1 VALUES (1); @@ -1430,7 +1430,7 @@ explain extended (select * from t1); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 Warnings: -Note 1003 (select `test`.`t1`.`s1` AS `s1` from `test`.`t1`) +Note 1003 (select 'tttt' AS `s1` from `test`.`t1`) (select * from t1); s1 tttt @@ -1497,7 +1497,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where 2 SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` < (select max(`test`.`t2`.`b`) from `test`.`t2`))) +Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` < (select max('0') from `test`.`t2`))) select * from t3 where a >= some (select b from t2); a explain extended select * from t3 where a >= some (select b from t2); @@ -1505,7 +1505,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where 2 SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` >= (select min(`test`.`t2`.`b`) from `test`.`t2`))) +Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` >= (select min('0') from `test`.`t2`))) select * from t3 where a >= all (select b from t2 group by 1); a 6 @@ -1516,7 +1516,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where 2 SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` < (select `test`.`t2`.`b` AS `b` from `test`.`t2` group by 1))) +Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` < (select '0' AS `b` from `test`.`t2` group by 1))) select * from t3 where a >= some (select b from t2 group by 1); a explain extended select * from t3 where a >= some (select b from t2 group by 1); @@ -1524,7 +1524,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where 2 SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found Warnings: -Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` >= (select `test`.`t2`.`b` AS `b` from `test`.`t2` group by 1))) +Note 1003 select `test`.`t3`.`a` AS `a` from `test`.`t3` where ((`test`.`t3`.`a` >= (select '0' AS `b` from `test`.`t2` group by 1))) select * from t3 where NULL >= any (select b from t2); a explain extended select * from t3 where NULL >= any (select b from t2); @@ -1618,7 +1618,7 @@ id select_type table type possible_keys key key_len ref rows Extra 3 UNION t1 system NULL NULL NULL NULL 1 NULL UNION RESULT ALL NULL NULL NULL NULL NULL Warnings: -Note 1003 select `test`.`t1`.`s1` AS `s1` from `test`.`t1` where 1 +Note 1003 select 'e' AS `s1` from `test`.`t1` where 1 drop table t1; CREATE TABLE t1 (number char(11) NOT NULL default '') ENGINE=MyISAM CHARSET=latin1; INSERT INTO t1 VALUES ('69294728265'),('18621828126'),('89356874041'),('95895001874'); diff --git a/mysql-test/r/union.result b/mysql-test/r/union.result index dc174e35c8f..602fc08e9fd 100644 --- a/mysql-test/r/union.result +++ b/mysql-test/r/union.result @@ -480,7 +480,7 @@ id select_type table type possible_keys key key_len ref rows Extra 2 UNION t2 const PRIMARY PRIMARY 4 const 1 NULL UNION RESULT ALL NULL NULL NULL NULL NULL Warnings: -Note 1003 (select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where (`test`.`t1`.`a` = 1)) union (select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where (`test`.`t2`.`a` = 1)) +Note 1003 (select '1' AS `a`,'1' AS `b` from `test`.`t1` where ('1' = 1)) union (select '1' AS `a`,'10' AS `b` from `test`.`t2` where ('1' = 1)) (select * from t1 where a=5) union (select * from t2 where a=1); a b 1 10 diff --git a/mysql-test/r/varbinary.result b/mysql-test/r/varbinary.result index 2b8a9c625a5..a41885a257d 100644 --- a/mysql-test/r/varbinary.result +++ b/mysql-test/r/varbinary.result @@ -15,7 +15,7 @@ explain extended select * from t1 where UNIQ=0x38afba1d73e6a18a; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 const UNIQ UNIQ 8 const 1 Warnings: -Note 1003 select `test`.`t1`.`ID` AS `ID`,`test`.`t1`.`UNIQ` AS `UNIQ` from `test`.`t1` where 1 +Note 1003 select '00000001' AS `ID`,'004084688022709641610' AS `UNIQ` from `test`.`t1` where 1 drop table t1; select x'hello'; 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 'x'hello'' at line 1 diff --git a/sql/item.cc b/sql/item.cc index c5d8a62761c..d7faa5f598e 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -1758,9 +1758,10 @@ void Item_ident::print(String *str) } } - if (!table_name || !field_name) + if (!table_name || !field_name || !field_name[0]) { - const char *nm= field_name ? field_name : name ? name : "tmp_field"; + const char *nm= (field_name && field_name[0]) ? + field_name : name ? name : "tmp_field"; append_identifier(thd, str, nm, (uint) strlen(nm)); return; } @@ -4900,6 +4901,22 @@ Item *Item_field::update_value_transformer(byte *select_arg) } +void Item_field::print(String *str) +{ + if (field && field->table->const_table) + { + char buff[MAX_FIELD_WIDTH]; + String tmp(buff,sizeof(buff),str->charset()); + field->val_str(&tmp); + str->append('\''); + str->append(tmp); + str->append('\''); + return; + } + Item_ident::print(str); +} + + Item_ref::Item_ref(Name_resolution_context *context_arg, Item **item, const char *table_name_arg, const char *field_name_arg, diff --git a/sql/item.h b/sql/item.h index 2a121523423..fb1a87d54fa 100644 --- a/sql/item.h +++ b/sql/item.h @@ -1303,6 +1303,7 @@ public: Item *safe_charset_converter(CHARSET_INFO *tocs); int fix_outer_field(THD *thd, Field **field, Item **reference); virtual Item *update_value_transformer(byte *select_arg); + void print(String *str); friend class Item_default_value; friend class Item_insert_value; friend class st_select_lex_unit; diff --git a/sql/sql_union.cc b/sql/sql_union.cc index 16df0059217..1ec724a6338 100644 --- a/sql/sql_union.cc +++ b/sql/sql_union.cc @@ -621,6 +621,12 @@ bool st_select_lex_unit::cleanup() join->tables= 0; } error|= fake_select_lex->cleanup(); + if (fake_select_lex->order_list.elements) + { + ORDER *ord; + for (ord= (ORDER*)fake_select_lex->order_list.first; ord; ord= ord->next) + (*ord->item)->cleanup(); + } } DBUG_RETURN(error); From ec4593f59a6fabd69fdea20c2f77bb5c4c775eb6 Mon Sep 17 00:00:00 2001 From: "igor@olga.mysql.com" <> Date: Sat, 10 Mar 2007 02:47:47 -0800 Subject: [PATCH 2/3] Fixed bug #26830: a crash for the query with a subselect containing ROLLUP. Crash happened because the function get_best_group_min_max detected joins with ROLLUP incorrectly. --- mysql-test/r/olap.result | 9 +++++++++ mysql-test/t/olap.test | 15 +++++++++++++++ sql/opt_range.cc | 2 +- 3 files changed, 25 insertions(+), 1 deletion(-) diff --git a/mysql-test/r/olap.result b/mysql-test/r/olap.result index a392de613f8..91cd15295c3 100644 --- a/mysql-test/r/olap.result +++ b/mysql-test/r/olap.result @@ -645,3 +645,12 @@ a LENGTH(a) COUNT(*) NULL NULL 2 DROP VIEW v1; DROP TABLE t1; +CREATE TABLE t1 (a int, KEY (a)); +INSERT INTO t1 VALUES (3), (1), (4), (1), (3), (1), (1); +SELECT * FROM (SELECT a, SUM(a) FROM t1 GROUP BY a WITH ROLLUP) as t; +a SUM(a) +1 4 +3 6 +4 4 +NULL 14 +DROP TABLE t1; diff --git a/mysql-test/t/olap.test b/mysql-test/t/olap.test index 4e5e7b72fc8..e6cbfe3166c 100644 --- a/mysql-test/t/olap.test +++ b/mysql-test/t/olap.test @@ -327,3 +327,18 @@ SELECT * FROM v1; DROP VIEW v1; DROP TABLE t1; + +# +# Bug #26830: derived table with ROLLUP +# + +CREATE TABLE t1 (a int, KEY (a)); +INSERT INTO t1 VALUES (3), (1), (4), (1), (3), (1), (1); + +SELECT * FROM (SELECT a, SUM(a) FROM t1 GROUP BY a WITH ROLLUP) as t; + +DROP TABLE t1; + + + + diff --git a/sql/opt_range.cc b/sql/opt_range.cc index dfb3af87c29..0e284850cbe 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -7504,7 +7504,7 @@ get_best_group_min_max(PARAM *param, SEL_TREE *tree) if ((join->tables != 1) || /* The query must reference one table. */ ((!join->group_list) && /* Neither GROUP BY nor a DISTINCT query. */ (!join->select_distinct)) || - (thd->lex->select_lex.olap == ROLLUP_TYPE)) /* Check (B3) for ROLLUP */ + (join->select_lex->olap == ROLLUP_TYPE)) /* Check (B3) for ROLLUP */ DBUG_RETURN(NULL); if (table->s->keys == 0) /* There are no indexes to use. */ DBUG_RETURN(NULL); From 6f6b9ae3ada5de135228eed2ccc8281c9f989be7 Mon Sep 17 00:00:00 2001 From: "evgen@moonbone.local" <> Date: Sat, 10 Mar 2007 19:55:34 +0300 Subject: [PATCH 3/3] Bug#15757: Wrong SUBSTRING() result when a tmp table was employed. When the SUBSTRING() function was used over a LONGTEXT field the max_length of the SUBSTRING() result was wrongly calculated and set to 0. As the max_length parameter is used while tmp field creation it limits the length of the result field and leads to printing an empty string instead of the correct result. Now the Item_func_substr::fix_length_and_dec() function correctly calculates the max_length parameter. --- mysql-test/r/func_str.result | 11 +++++++++++ mysql-test/t/func_str.test | 11 +++++++++++ sql/item_strfunc.cc | 7 +++---- 3 files changed, 25 insertions(+), 4 deletions(-) diff --git a/mysql-test/r/func_str.result b/mysql-test/r/func_str.result index d09d3aeb529..1ecdea851ce 100644 --- a/mysql-test/r/func_str.result +++ b/mysql-test/r/func_str.result @@ -1946,4 +1946,15 @@ NULL SELECT UNHEX('G') IS NULL; UNHEX('G') IS NULL 1 +create table t1(f1 longtext); +insert into t1 values ("123"),("456"); +select substring(f1,1,1) from t1 group by 1; +substring(f1,1,1) +1 +4 +create table t2(f1 varchar(3)); +insert into t1 values ("123"),("456"); +select substring(f1,4,1), substring(f1,-4,1) from t2; +substring(f1,4,1) substring(f1,-4,1) +drop table t1,t2; End of 5.0 tests diff --git a/mysql-test/t/func_str.test b/mysql-test/t/func_str.test index 2e76dc2ca31..4b44669cb91 100644 --- a/mysql-test/t/func_str.test +++ b/mysql-test/t/func_str.test @@ -1014,4 +1014,15 @@ select lpad('abc', cast(5 as unsigned integer), 'x'); SELECT UNHEX('G'); SELECT UNHEX('G') IS NULL; +# +# Bug#15757: Wrong SUBSTRING() result when a tmp table was employed. +# +create table t1(f1 longtext); +insert into t1 values ("123"),("456"); +select substring(f1,1,1) from t1 group by 1; +create table t2(f1 varchar(3)); +insert into t1 values ("123"),("456"); +select substring(f1,4,1), substring(f1,-4,1) from t2; +drop table t1,t2; + --echo End of 5.0 tests diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc index 385f4ad9770..1d1f433789b 100644 --- a/sql/item_strfunc.cc +++ b/sql/item_strfunc.cc @@ -1184,11 +1184,10 @@ void Item_func_substr::fix_length_and_dec() if (args[1]->const_item()) { int32 start= (int32) args[1]->val_int(); - start= (int32)((start < 0) ? max_length + start : start - 1); - if (start < 0 || start >= (int32) max_length) - max_length=0; /* purecov: inspected */ + if (start < 0) + max_length= ((uint)(-start) > max_length) ? 0 : (uint)(-start); else - max_length-= (uint) start; + max_length-= min((uint)(start - 1), max_length); } if (arg_count == 3 && args[2]->const_item()) {