diff options
| -rw-r--r-- | mysql-test/main/explain.result | 62 | ||||
| -rw-r--r-- | mysql-test/main/explain.test | 39 | ||||
| -rw-r--r-- | sql/item_subselect.cc | 9 | ||||
| -rw-r--r-- | sql/item_subselect.h | 1 |
4 files changed, 110 insertions, 1 deletions
diff --git a/mysql-test/main/explain.result b/mysql-test/main/explain.result index f593e0dfaba..fb3584d853b 100644 --- a/mysql-test/main/explain.result +++ b/mysql-test/main/explain.result @@ -407,3 +407,65 @@ id select_type table type possible_keys key key_len ref rows Extra 2 SUBQUERY t1 system NULL NULL NULL NULL 1 drop table t1, t2; # End of 10.1 tests +# +# MDEV-27957: Select from view with subselect fails with lost connection +# +CREATE TABLE t1 (id INT PRIMARY KEY); +INSERT INTO t1 VALUES (1),(2); +CREATE VIEW v1 AS SELECT +1 IN ( +SELECT +(SELECT COUNT(id) +FROM t1 +WHERE t1_outer.id <> id +) AS f +FROM +t1 AS t1_outer +GROUP BY f +); +explain extended SELECT +1 IN ( +SELECT +(SELECT COUNT(id) +FROM t1 +WHERE t1_outer.id <> id +) AS f +FROM +t1 AS t1_outer +GROUP BY f +); +id select_type table type possible_keys key key_len ref rows filtered Extra +1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL No tables used +2 SUBQUERY t1_outer index NULL PRIMARY 4 NULL 2 100.00 Using where; Using index +3 DEPENDENT SUBQUERY t1 index NULL PRIMARY 4 NULL 2 100.00 Using where; Using index +Warnings: +Note 1276 Field or reference 'test.t1_outer.id' of SELECT #3 was resolved in SELECT #2 +Note 1003 /* select#1 */ select <in_optimizer>(1,<exists>(/* select#2 */ select <expr_cache><`t1_outer`.`id`>((/* select#3 */ select count(`test`.`t1`.`id`) from `test`.`t1` where `t1_outer`.`id` <> `test`.`t1`.`id`)) from `test`.`t1` `t1_outer` where 1 = (/* select#3 */ select count(`test`.`t1`.`id`) from `test`.`t1` where `t1_outer`.`id` <> `test`.`t1`.`id`) or (/* select#3 */ select count(`test`.`t1`.`id`) from `test`.`t1` where `t1_outer`.`id` <> `test`.`t1`.`id`) is null having (/* select#3 */ select count(`test`.`t1`.`id`) from `test`.`t1` where `t1_outer`.`id` <> `test`.`t1`.`id`) is null)) AS `1 IN ( +SELECT +(SELECT COUNT(id) +FROM t1 +WHERE t1_outer.id <> id +) AS f +FROM +t1 AS t1_outer +GROUP BY f +)` +SELECT * FROM v1; +Name_exp_1 +1 +explain extended +SELECT * FROM v1; +id select_type table type possible_keys key key_len ref rows filtered Extra +1 PRIMARY <derived2> system NULL NULL NULL NULL 1 100.00 +2 DERIVED NULL NULL NULL NULL NULL NULL NULL NULL No tables used +3 SUBQUERY t1_outer index NULL PRIMARY 4 NULL 2 100.00 Using where; Using index +4 DEPENDENT SUBQUERY t1 index NULL PRIMARY 4 NULL 2 100.00 Using where; Using index +Warnings: +Note 1276 Field or reference 'test.t1_outer.id' of SELECT #4 was resolved in SELECT #3 +Note 1276 Field or reference 'test.t1_outer.id' of SELECT #5 was resolved in SELECT #3 +Note 1003 /* select#1 */ select 1 AS `Name_exp_1` from dual +DROP VIEW v1; +DROP TABLE t1; +# +# End of 10.3 tests +# diff --git a/mysql-test/main/explain.test b/mysql-test/main/explain.test index d5be354c852..416abf9888d 100644 --- a/mysql-test/main/explain.test +++ b/mysql-test/main/explain.test @@ -333,3 +333,42 @@ explain replace into t2 select 100, (select a from t1); drop table t1, t2; --echo # End of 10.1 tests + +--echo # +--echo # MDEV-27957: Select from view with subselect fails with lost connection +--echo # + +CREATE TABLE t1 (id INT PRIMARY KEY); +INSERT INTO t1 VALUES (1),(2); + +CREATE VIEW v1 AS SELECT + 1 IN ( + SELECT + (SELECT COUNT(id) + FROM t1 + WHERE t1_outer.id <> id + ) AS f + FROM + t1 AS t1_outer + GROUP BY f + ); +explain extended SELECT + 1 IN ( + SELECT + (SELECT COUNT(id) + FROM t1 + WHERE t1_outer.id <> id + ) AS f + FROM + t1 AS t1_outer + GROUP BY f + ); +SELECT * FROM v1; +explain extended +SELECT * FROM v1; +DROP VIEW v1; +DROP TABLE t1; + +--echo # +--echo # End of 10.3 tests +--echo # diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc index a5ad00c9bb9..19a13b24cd1 100644 --- a/sql/item_subselect.cc +++ b/sql/item_subselect.cc @@ -3679,6 +3679,13 @@ bool subselect_union_engine::is_executed() const return unit->executed; } + +int subselect_union_engine::get_identifier() +{ + return unit->first_select()->select_number; +} + + void subselect_union_engine::force_reexecution() { unit->executed= false; @@ -6872,7 +6879,7 @@ void Item_subselect::init_expr_cache_tracker(THD *thd) Explain_query *qw= thd->lex->explain; DBUG_ASSERT(qw); - Explain_node *node= qw->get_node(unit->first_select()->select_number); + Explain_node *node= qw->get_node(engine->get_identifier()); if (!node) return; DBUG_ASSERT(expr_cache->type() == Item::EXPR_CACHE_ITEM); diff --git a/sql/item_subselect.h b/sql/item_subselect.h index 16c683b27e0..35ad8e039c6 100644 --- a/sql/item_subselect.h +++ b/sql/item_subselect.h @@ -929,6 +929,7 @@ public: bool temp= FALSE); bool no_tables(); bool is_executed() const; + int get_identifier(); void force_reexecution(); bool no_rows(); virtual enum_engine_type engine_type() { return UNION_ENGINE; } |