From 2594da7a33580bf03590502a011679c878487d0c Mon Sep 17 00:00:00 2001 From: Sergei Petrunia Date: Fri, 5 May 2023 11:16:23 +0300 Subject: MDEV-31194: Server crash or assertion failure with join_cache_level=4 The problem, introduced in patch for MDEV-26301: When check_join_cache_usage() decides not to use join buffer, it must adjust the access method accordingly. For BNL-H joins this means switching from pseudo-"ref access"(with index=MAX_KEY) to some other access method. Failing to do this will cause assertions down the line when code that is not aware of BNL-H will try to initialize index use for ref access with index=MAX_KEY. The fix is to follow the regular code path to disable the join buffer for the join_tab ("goto no_join_cache") instead of just returning from check_join_cache_usage(). --- mysql-test/main/derived_split_innodb.result | 16 ++++++++++++++++ mysql-test/main/derived_split_innodb.test | 23 +++++++++++++++++++++++ sql/sql_select.cc | 2 +- 3 files changed, 40 insertions(+), 1 deletion(-) diff --git a/mysql-test/main/derived_split_innodb.result b/mysql-test/main/derived_split_innodb.result index a2dd1470d15..736e6a2c020 100644 --- a/mysql-test/main/derived_split_innodb.result +++ b/mysql-test/main/derived_split_innodb.result @@ -794,4 +794,20 @@ a b a b a b grp_id count(*) 5 5 5 2 5 3 5 100 drop table t1,t2,t3; drop table t10, t11; +# +# MDEV-31194: Server crash or assertion failure with join_cache_level=4 +# (a followup to the above bug, MDEV-26301) +# +CREATE TABLE t1 (a INT); +INSERT INTO t1 VALUES (3),(4); +CREATE TABLE t2 (id INT PRIMARY KEY) ENGINE=Aria; +INSERT INTO t2 VALUES (1),(2); +set @tmp1= @@optimizer_switch, @tmp2= @@join_cache_level; +set +optimizer_switch= 'derived_with_keys=off', +join_cache_level= 4; +SELECT t1.* FROM t1 JOIN (SELECT id, COUNT(*) FROM t2 GROUP BY id) sq ON sq.id= t1.a; +a +set optimizer_switch= @tmp1, join_cache_level= @tmp2; +DROP TABLE t1, t2; # End of 10.4 tests diff --git a/mysql-test/main/derived_split_innodb.test b/mysql-test/main/derived_split_innodb.test index a26c9af4e64..b8dd5ad20e1 100644 --- a/mysql-test/main/derived_split_innodb.test +++ b/mysql-test/main/derived_split_innodb.test @@ -439,4 +439,27 @@ eval $q; drop table t1,t2,t3; drop table t10, t11; + +--echo # +--echo # MDEV-31194: Server crash or assertion failure with join_cache_level=4 +--echo # (a followup to the above bug, MDEV-26301) +--echo # +CREATE TABLE t1 (a INT); +INSERT INTO t1 VALUES (3),(4); + +CREATE TABLE t2 (id INT PRIMARY KEY) ENGINE=Aria; +INSERT INTO t2 VALUES (1),(2); + +set @tmp1= @@optimizer_switch, @tmp2= @@join_cache_level; +set + optimizer_switch= 'derived_with_keys=off', + join_cache_level= 4; + +SELECT t1.* FROM t1 JOIN (SELECT id, COUNT(*) FROM t2 GROUP BY id) sq ON sq.id= t1.a; + +set optimizer_switch= @tmp1, join_cache_level= @tmp2; + +# Cleanup +DROP TABLE t1, t2; + --echo # End of 10.4 tests diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 5e2ce06add7..bfe17bb43e1 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -12873,7 +12873,7 @@ uint check_join_cache_usage(JOIN_TAB *tab, join->return_tab= 0; if (tab->no_forced_join_cache) - return 0; + goto no_join_cache; /* Don't use join cache if @@join_cache_level==0 or this table is the first -- cgit v1.2.1