From 1b349cf85fecaf22b6b16dc24541c345cd5a89fe Mon Sep 17 00:00:00 2001 From: "sergefp@mysql.com" <> Date: Sat, 6 May 2006 13:15:00 +0400 Subject: [PATCH] BUG#16798: Inapplicable ref_or_null query plan and bad query result on random occasions The bug was as follows: When merge_key_fields() encounters "t.key=X OR t.key=Y" it will try to join them into ref_or_null access via "t.key=X OR NULL". In order to make this inference it checks if Y<=>NULL, ignoring the fact that value of Y may be not yet known. The fix is that the check if Y<=>NULL is made only if value of Y is known (i.e. it is a constant). TODO: When merging to 5.0, replace used_tables() with const_item() everywhere in merge_key_fields(). --- mysql-test/r/innodb_mysql.result | 57 +++++++++++++++++++++++++++++++- mysql-test/t/innodb_mysql.test | 56 ++++++++++++++++++++++++++++++- sql/sql_select.cc | 3 +- 3 files changed, 113 insertions(+), 3 deletions(-) diff --git a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result index 878c5cb5451..2a4e3555e3b 100644 --- a/mysql-test/r/innodb_mysql.result +++ b/mysql-test/r/innodb_mysql.result @@ -1 +1,56 @@ -drop table if exists t1; +drop table if exists t1,t2; +create table t1 ( +c_id int(11) not null default '0', +org_id int(11) default null, +unique key contacts$c_id (c_id), +key contacts$org_id (org_id) +) engine=innodb; +insert into t1 values +(2,null),(120,null),(141,null),(218,7), (128,1), +(151,2),(234,2),(236,2),(243,2),(255,2),(259,2),(232,3),(235,3),(238,3), +(246,3),(253,3),(269,3),(285,3),(291,3),(293,3),(131,4),(230,4),(231,4); +create table t2 ( +slai_id int(11) not null default '0', +owner_tbl int(11) default null, +owner_id int(11) default null, +sla_id int(11) default null, +inc_web int(11) default null, +inc_email int(11) default null, +inc_chat int(11) default null, +inc_csr int(11) default null, +inc_total int(11) default null, +time_billed int(11) default null, +activedate timestamp null default null, +expiredate timestamp null default null, +state int(11) default null, +sla_set int(11) default null, +unique key t2$slai_id (slai_id), +key t2$owner_id (owner_id), +key t2$sla_id (sla_id) +) engine=innodb; +insert into t2(slai_id, owner_tbl, owner_id, sla_id) values +(1,3,1,1), (3,3,10,2), (4,3,3,6), (5,3,2,5), (6,3,8,3), (7,3,9,7), +(8,3,6,8), (9,3,4,9), (10,3,5,10), (11,3,11,11), (12,3,7,12); +flush tables; +select si.slai_id +from t1 c join t2 si on +((si.owner_tbl = 3 and si.owner_id = c.org_id) or +( si.owner_tbl = 2 and si.owner_id = c.c_id)) +where +c.c_id = 218 and expiredate is null; +slai_id +12 +select * from t1 where org_id is null; +c_id org_id +2 NULL +120 NULL +141 NULL +select si.slai_id +from t1 c join t2 si on +((si.owner_tbl = 3 and si.owner_id = c.org_id) or +( si.owner_tbl = 2 and si.owner_id = c.c_id)) +where +c.c_id = 218 and expiredate is null; +slai_id +12 +drop table t1, t2; diff --git a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test index b942b9fbc0d..f31e4d64789 100644 --- a/mysql-test/t/innodb_mysql.test +++ b/mysql-test/t/innodb_mysql.test @@ -1,5 +1,59 @@ -- source include/have_innodb.inc --disable_warnings -drop table if exists t1; +drop table if exists t1,t2; --enable_warnings + +# BUG#16798: Uninitialized row buffer reads in ref-or-null optimizer +# (repeatable only w/innodb). +create table t1 ( + c_id int(11) not null default '0', + org_id int(11) default null, + unique key contacts$c_id (c_id), + key contacts$org_id (org_id) +) engine=innodb; +insert into t1 values + (2,null),(120,null),(141,null),(218,7), (128,1), + (151,2),(234,2),(236,2),(243,2),(255,2),(259,2),(232,3),(235,3),(238,3), + (246,3),(253,3),(269,3),(285,3),(291,3),(293,3),(131,4),(230,4),(231,4); + +create table t2 ( + slai_id int(11) not null default '0', + owner_tbl int(11) default null, + owner_id int(11) default null, + sla_id int(11) default null, + inc_web int(11) default null, + inc_email int(11) default null, + inc_chat int(11) default null, + inc_csr int(11) default null, + inc_total int(11) default null, + time_billed int(11) default null, + activedate timestamp null default null, + expiredate timestamp null default null, + state int(11) default null, + sla_set int(11) default null, + unique key t2$slai_id (slai_id), + key t2$owner_id (owner_id), + key t2$sla_id (sla_id) +) engine=innodb; +insert into t2(slai_id, owner_tbl, owner_id, sla_id) values + (1,3,1,1), (3,3,10,2), (4,3,3,6), (5,3,2,5), (6,3,8,3), (7,3,9,7), + (8,3,6,8), (9,3,4,9), (10,3,5,10), (11,3,11,11), (12,3,7,12); + +flush tables; +select si.slai_id +from t1 c join t2 si on + ((si.owner_tbl = 3 and si.owner_id = c.org_id) or + ( si.owner_tbl = 2 and si.owner_id = c.c_id)) +where + c.c_id = 218 and expiredate is null; + +select * from t1 where org_id is null; +select si.slai_id +from t1 c join t2 si on + ((si.owner_tbl = 3 and si.owner_id = c.org_id) or + ( si.owner_tbl = 2 and si.owner_id = c.c_id)) +where + c.c_id = 218 and expiredate is null; + +drop table t1, t2; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 46dba61cfc5..4995a164226 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -2090,7 +2090,8 @@ merge_key_fields(KEY_FIELD *start,KEY_FIELD *new_fields,KEY_FIELD *end, new_fields->null_rejecting); } else if (old->eq_func && new_fields->eq_func && - (old->val->is_null() || new_fields->val->is_null())) + ((!old->val->used_tables() && old->val->is_null()) || + new_fields->val->is_null())) { /* field = expression OR field IS NULL */ old->level= and_level;