From aa713f5ae20513b0c4d9a74ea3ba3ea3bbdcd719 Mon Sep 17 00:00:00 2001 From: Igor Babaev Date: Tue, 9 May 2023 21:20:10 -0700 Subject: [PATCH] MDEV-31224 Crash with EXPLAIN EXTENDED for multi-table update of system table EXPLAIN EXTENDED should always print the field item used in the left part of an equality expression from the SET clause of an update statement as a reference to table column. Approved by Oleksandr Byelkin --- mysql-test/main/explain_non_select.result | 19 ++++++++++++++++++ mysql-test/main/explain_non_select.test | 20 +++++++++++++++++++ .../main/myisam_explain_non_select_all.result | 4 ++-- sql/sql_select.cc | 2 +- 4 files changed, 42 insertions(+), 3 deletions(-) diff --git a/mysql-test/main/explain_non_select.result b/mysql-test/main/explain_non_select.result index d60f10f85c8..1200a3f9400 100644 --- a/mysql-test/main/explain_non_select.result +++ b/mysql-test/main/explain_non_select.result @@ -277,3 +277,22 @@ EXECUTE stmt; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 ALL NULL NULL NULL NULL 2 drop table t1,t2; +# +# MDEV-31224: EXPLAIN EXTENDED for multi-table update of system table +# +CREATE TABLE t1 (a INT); +INSERT INTO t1 VALUES (1),(2); +CREATE TABLE t2 (b INT) ENGINE=MyISAM; +INSERT INTO t2 VALUES (3); +EXPLAIN EXTENDED UPDATE t1, t2 SET b = 4 WHERE a IN (6,2); +id select_type table type possible_keys key key_len ref rows filtered Extra +1 SIMPLE t2 system NULL NULL NULL NULL 1 100.00 +1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where +Warnings: +Note 1003 update `test`.`t1` set `test`.`t2`.`b` = 4 where `test`.`t1`.`a` in (6,2) +UPDATE t1, t2 SET b = 4 WHERE a IN (6,2); +SELECT * from t2; +b +4 +DROP TABLE t1, t2; +# End of 10.4 tests diff --git a/mysql-test/main/explain_non_select.test b/mysql-test/main/explain_non_select.test index d9ff0fb7245..f87a5d9ec8d 100644 --- a/mysql-test/main/explain_non_select.test +++ b/mysql-test/main/explain_non_select.test @@ -250,3 +250,23 @@ PREPARE stmt FROM 'EXPLAIN INSERT INTO t1 SELECT * FROM t2'; EXECUTE stmt; drop table t1,t2; +--echo # +--echo # MDEV-31224: EXPLAIN EXTENDED for multi-table update of system table +--echo # + +CREATE TABLE t1 (a INT); +INSERT INTO t1 VALUES (1),(2); + +CREATE TABLE t2 (b INT) ENGINE=MyISAM; +INSERT INTO t2 VALUES (3); + +let $q= +UPDATE t1, t2 SET b = 4 WHERE a IN (6,2); + +eval EXPLAIN EXTENDED $q; +eval $q; +SELECT * from t2; + +DROP TABLE t1, t2; + +--echo # End of 10.4 tests diff --git a/mysql-test/main/myisam_explain_non_select_all.result b/mysql-test/main/myisam_explain_non_select_all.result index 3ca9629d027..b515cb4fd83 100644 --- a/mysql-test/main/myisam_explain_non_select_all.result +++ b/mysql-test/main/myisam_explain_non_select_all.result @@ -2689,7 +2689,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 Const row not found 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Warnings: -Note 1003 update `test`.`t1` set NULL = 10 +Note 1003 update `test`.`t1` set `test`.`t2`.`c2` = 10 # Status of EXPLAIN EXTENDED query Variable_name Value Handler_read_key 7 @@ -2734,7 +2734,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 Const row not found 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where Warnings: -Note 1003 update `test`.`t1` set NULL = 10 where `test`.`t1`.`c3` = 10 +Note 1003 update `test`.`t1` set `test`.`t2`.`c2` = 10 where `test`.`t1`.`c3` = 10 # Status of EXPLAIN EXTENDED query Variable_name Value Handler_read_key 7 diff --git a/sql/sql_select.cc b/sql/sql_select.cc index bfe17bb43e1..cb60b3442d8 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -28138,7 +28138,7 @@ void st_select_lex::print_set_clause(THD *thd, String *str, else str->append(','); - item->print(str, query_type); + item->print(str, (enum_query_type) (query_type | QT_NO_DATA_EXPANSION)); str->append(STRING_WITH_LEN(" = ")); val->print(str, query_type); }