revision-id: d140d276244508d7f2e69a3c1a23e0b09201f71a (mariadb-10.2.43-13-gd140d276244) parent(s): 24ec144c63b36402adaff2bc12aaabefa40bdd51 author: Sergei Petrunia committer: Sergei Petrunia timestamp: 2022-02-21 18:44:11 +0300 message: MDEV-22377: Subquery in an UPDATE query uses full scan instead of range [Patch idea by Igor Babaev] Symptom: for IN (SELECT ...) subqueries using IN-to-EXISTS transformation, the optimizer was unable to make inferences using multiple equalities. The cause is code Item_in_subselect::inject_in_to_exists_cond() which may break invariants that Multiple-Equality code relies on. In particular, it may produce a WHERE condition with an empty Item_cond::m_cond_equal. Fixed this by making Item_cond::m_cond_equal. --- mysql-test/r/subselect2.result | 2 +- mysql-test/r/subselect3.result | 4 +-- mysql-test/r/subselect3_jcl6.result | 4 +-- mysql-test/r/subselect4.result | 40 ++++++++++++++++++++++++++- mysql-test/r/subselect_mat_cost_bugs.result | 4 +-- mysql-test/t/subselect4.test | 43 +++++++++++++++++++++++++++++ sql/item_subselect.cc | 9 ++---- 7 files changed, 92 insertions(+), 14 deletions(-) diff --git a/mysql-test/r/subselect2.result b/mysql-test/r/subselect2.result index 155d5ab2a50..91d3e445b48 100644 --- a/mysql-test/r/subselect2.result +++ b/mysql-test/r/subselect2.result @@ -262,7 +262,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2c ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (incremental, BNL join) Warnings: Note 1276 Field or reference 'test.t1.a' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`c1` AS `c1` from `test`.`t1` where !<expr_cache><`test`.`t1`.`c1`,`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`c1`,<exists>(select `test`.`t2a`.`c2` from `test`.`t2` `t2a` join `test`.`t2` `t2b` join `test`.`t2` `t2c` where (`test`.`t2b`.`m` <> `test`.`t1`.`a` or `test`.`t2b`.`m` = `test`.`t2a`.`m`) and trigcond(<cache>(`test`.`t1`.`c1`) = `test`.`t2a`.`c2` or `test`.`t2a`.`c2` is null) and `test`.`t2c`.`c2` = `test`.`t2b`.`c2` and `test`.`t2b`.`n` = `test`.`t2a`.`m` having trigcond(`test`.`t2a`.`c2` is null)))) +Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`c1` AS `c1` from `test`.`t1` where !<expr_cache><`test`.`t1`.`c1`,`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`c1`,<exists>(select `test`.`t2a`.`c2` from `test`.`t2` `t2a` join `test`.`t2` `t2b` join `test`.`t2` `t2c` where `test`.`t2c`.`c2` = `test`.`t2b`.`c2` and `test`.`t2b`.`n` = `test`.`t2a`.`m` and (`test`.`t2b`.`m` <> `test`.`t1`.`a` or `test`.`t2b`.`m` = `test`.`t2a`.`m`) and trigcond(<cache>(`test`.`t1`.`c1`) = `test`.`t2a`.`c2` or `test`.`t2a`.`c2` is null) having trigcond(`test`.`t2a`.`c2` is null)))) DROP TABLE t1,t2; # # MDEV-614, also MDEV-536, also LP:1050806: diff --git a/mysql-test/r/subselect3.result b/mysql-test/r/subselect3.result index 8d33e4e1606..d92626380ef 100644 --- a/mysql-test/r/subselect3.result +++ b/mysql-test/r/subselect3.result @@ -169,7 +169,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2 ref a a 5 test.t1.b 1 100.00 Using where Warnings: Note 1276 Field or reference 'test.t3.oref' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a` or `test`.`t1`.`a` is null) and `test`.`t2`.`a` = `test`.`t1`.`b` having trigcond(`test`.`t1`.`a` is null)))) AS `Z` from `test`.`t3` +Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`b` and `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a` or `test`.`t1`.`a` is null) having trigcond(`test`.`t1`.`a` is null)))) AS `Z` from `test`.`t3` drop table t1, t2, t3; create table t1 (a int NOT NULL, b int NOT NULL, key(a)); insert into t1 values @@ -197,7 +197,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2 ref a a 4 test.t1.b 1 100.00 Using where Warnings: Note 1276 Field or reference 'test.t3.oref' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a`) and `test`.`t2`.`a` = `test`.`t1`.`b`))) AS `Z` from `test`.`t3` +Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`b` and `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a`)))) AS `Z` from `test`.`t3` drop table t1,t2,t3; create table t1 (oref int, grp int); insert into t1 (oref, grp) values diff --git a/mysql-test/r/subselect3_jcl6.result b/mysql-test/r/subselect3_jcl6.result index 6d1e305bc49..2df3f2eea35 100644 --- a/mysql-test/r/subselect3_jcl6.result +++ b/mysql-test/r/subselect3_jcl6.result @@ -172,7 +172,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2 ref a a 5 test.t1.b 1 100.00 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan Warnings: Note 1276 Field or reference 'test.t3.oref' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a` or `test`.`t1`.`a` is null) and `test`.`t2`.`a` = `test`.`t1`.`b` having trigcond(`test`.`t1`.`a` is null)))) AS `Z` from `test`.`t3` +Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`b` and `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a` or `test`.`t1`.`a` is null) having trigcond(`test`.`t1`.`a` is null)))) AS `Z` from `test`.`t3` drop table t1, t2, t3; create table t1 (a int NOT NULL, b int NOT NULL, key(a)); insert into t1 values @@ -200,7 +200,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2 ref a a 4 test.t1.b 1 100.00 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan Warnings: Note 1276 Field or reference 'test.t3.oref' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a`) and `test`.`t2`.`a` = `test`.`t1`.`b`))) AS `Z` from `test`.`t3` +Note 1003 select `test`.`t3`.`a` AS `a`,`test`.`t3`.`oref` AS `oref`,<expr_cache><`test`.`t3`.`a`,`test`.`t3`.`oref`>(<in_optimizer>(`test`.`t3`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`b` and `test`.`t2`.`b` = `test`.`t3`.`oref` and trigcond(<cache>(`test`.`t3`.`a`) = `test`.`t1`.`a`)))) AS `Z` from `test`.`t3` drop table t1,t2,t3; create table t1 (oref int, grp int); insert into t1 (oref, grp) values diff --git a/mysql-test/r/subselect4.result b/mysql-test/r/subselect4.result index 2657977dae7..43e698d2b56 100644 --- a/mysql-test/r/subselect4.result +++ b/mysql-test/r/subselect4.result @@ -2351,7 +2351,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00 2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 2 100.00 Using where Warnings: -Note 1003 select 3 AS `f` from dual where !<expr_cache><3>(<in_optimizer>(3,<exists>(select `test`.`t1`.`b` from `test`.`t1` where (`test`.`t1`.`c` = 'USA' or `test`.`t1`.`c` <> 'USA') and trigcond(<cache>(3) = `test`.`t1`.`b` or `test`.`t1`.`b` is null) and `test`.`t1`.`b` = `test`.`t1`.`a` having trigcond(`test`.`t1`.`b` is null)))) +Note 1003 select 3 AS `f` from dual where !<expr_cache><3>(<in_optimizer>(3,<exists>(select `test`.`t1`.`b` from `test`.`t1` where `test`.`t1`.`b` = `test`.`t1`.`a` and (`test`.`t1`.`c` = 'USA' or `test`.`t1`.`c` <> 'USA') and trigcond(<cache>(3) = `test`.`t1`.`b` or `test`.`t1`.`b` is null) having trigcond(`test`.`t1`.`b` is null)))) SELECT * FROM t2 WHERE f NOT IN (SELECT b FROM t1 WHERE 0 OR (c IN ('USA') OR c NOT IN ('USA')) AND a = b); @@ -2803,4 +2803,42 @@ FROM (t1 JOIN t1 AS ref_t1 ON (t1.i1 > (SELECT ref_t1.i1 AS c0 FROM t1 b ORDER BY -c0))); ERROR 21000: Subquery returns more than 1 row DROP TABLE t1; +# +# MDEV-22377: Subquery in an UPDATE query uses full scan instead of range +# +CREATE TABLE t1 ( +key1 varchar(30) NOT NULL, +col1 int(11) NOT NULL, +filler char(100) +); +insert into t1 select seq, seq, seq from seq_1_to_100; +CREATE TABLE t10 ( +key1 varchar(30) NOT NULL, +col1 int, +filler char(100), +PRIMARY KEY (key1) +); +insert into t10 select seq, seq, seq from seq_1_to_1000; +CREATE TABLE t11 ( +key1 varchar(30) NOT NULL, +filler char(100), +PRIMARY KEY (key1) +); +insert into t11 select seq, seq from seq_1_to_1000; +set @tmp_os=@@optimizer_switch; +set optimizer_switch='semijoin=off,materialization=off'; +# Must use range access (not full scan) for table tms: +explain select * from t1 hist +WHERE +key1 IN ('1','2','3','4','5','6','7','8','9','10') AND +hist.col1 NOT IN (SELECT tn.col1 +FROM t10 tn JOIN t11 tms ON tms.key1 = tn.key1 +WHERE tn.key1 IN ('1','2','3','4','5','6','7','8','9','10') +); +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY hist ALL NULL NULL NULL NULL 100 Using where +2 DEPENDENT SUBQUERY tms range PRIMARY PRIMARY 32 NULL 10 Using where; Using index +2 DEPENDENT SUBQUERY tn eq_ref PRIMARY PRIMARY 32 test.tms.key1 1 Using where +set optimizer_switch=@tmp_os; +drop table t1, t10, t11; # End of 10.2 tests diff --git a/mysql-test/r/subselect_mat_cost_bugs.result b/mysql-test/r/subselect_mat_cost_bugs.result index fd768b1efd4..87cbc1bb078 100644 --- a/mysql-test/r/subselect_mat_cost_bugs.result +++ b/mysql-test/r/subselect_mat_cost_bugs.result @@ -100,7 +100,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra 2 DEPENDENT SUBQUERY t2 index c3 c3 9 NULL 2 100.00 Using where; Using index; Using join buffer (flat, BNL join) Warnings: Note 1276 Field or reference 'test.t1.pk' of SELECT #2 was resolved in SELECT #1 -Note 1003 select `test`.`t1`.`pk` AS `pk` from `test`.`t1` where <expr_cache><`test`.`t1`.`c1`,`test`.`t1`.`pk`>(<in_optimizer>(`test`.`t1`.`c1`,<exists>(select `test`.`t1a`.`c1` from `test`.`t1b` join `test`.`t2` left join `test`.`t1a` on(`test`.`t1a`.`c2` = `test`.`t1b`.`pk` and 2) where `test`.`t1`.`pk` <> 0 and <cache>(`test`.`t1`.`c1`) = `test`.`t1a`.`c1` and `test`.`t2`.`c3` = `test`.`t1b`.`c4`))) +Note 1003 select `test`.`t1`.`pk` AS `pk` from `test`.`t1` where <expr_cache><`test`.`t1`.`c1`,`test`.`t1`.`pk`>(<in_optimizer>(`test`.`t1`.`c1`,<exists>(select `test`.`t1a`.`c1` from `test`.`t1b` join `test`.`t2` left join `test`.`t1a` on(`test`.`t1a`.`c2` = `test`.`t1b`.`pk` and 2) where `test`.`t2`.`c3` = `test`.`t1b`.`c4` and `test`.`t1`.`pk` <> 0 and <cache>(`test`.`t1`.`c1`) = `test`.`t1a`.`c1`))) SELECT pk FROM t1 WHERE c1 IN @@ -363,7 +363,7 @@ AND a = SOME (SELECT b FROM t5)); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where 2 DEPENDENT SUBQUERY t5 index c c 10 NULL 2 Using where; Using index; Start temporary -2 DEPENDENT SUBQUERY t4 eq_ref PRIMARY PRIMARY 4 test.t5.b 1 Using index condition; Using where; End temporary +2 DEPENDENT SUBQUERY t4 eq_ref PRIMARY PRIMARY 4 test.t5.b 1 Using where; End temporary SELECT * FROM t3 WHERE t3.b > ALL ( diff --git a/mysql-test/t/subselect4.test b/mysql-test/t/subselect4.test index 93389571c5c..1313d2e49e7 100644 --- a/mysql-test/t/subselect4.test +++ b/mysql-test/t/subselect4.test @@ -2308,4 +2308,47 @@ FROM (t1 JOIN t1 AS ref_t1 ON DROP TABLE t1; +--echo # +--echo # MDEV-22377: Subquery in an UPDATE query uses full scan instead of range +--echo # + +CREATE TABLE t1 ( + key1 varchar(30) NOT NULL, + col1 int(11) NOT NULL, + filler char(100) +); +insert into t1 select seq, seq, seq from seq_1_to_100; + +CREATE TABLE t10 ( + key1 varchar(30) NOT NULL, + col1 int, + filler char(100), + PRIMARY KEY (key1) +); +insert into t10 select seq, seq, seq from seq_1_to_1000; + +CREATE TABLE t11 ( + key1 varchar(30) NOT NULL, + filler char(100), + PRIMARY KEY (key1) +); +insert into t11 select seq, seq from seq_1_to_1000; + + +set @tmp_os=@@optimizer_switch; +set optimizer_switch='semijoin=off,materialization=off'; + +--echo # Must use range access (not full scan) for table tms: +explain select * from t1 hist +WHERE + key1 IN ('1','2','3','4','5','6','7','8','9','10') AND + hist.col1 NOT IN (SELECT tn.col1 + FROM t10 tn JOIN t11 tms ON tms.key1 = tn.key1 + WHERE tn.key1 IN ('1','2','3','4','5','6','7','8','9','10') + ); + +set optimizer_switch=@tmp_os; + +drop table t1, t10, t11; + --echo # End of 10.2 tests diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc index 25621dfe104..92ba085af5b 100644 --- a/sql/item_subselect.cc +++ b/sql/item_subselect.cc @@ -2769,12 +2769,9 @@ bool Item_in_subselect::inject_in_to_exists_cond(JOIN *join_arg) { /* The argument list of the top-level AND may change after fix fields. */ and_args= ((Item_cond*) join_arg->conds)->argument_list(); - List_iterator<Item_equal> li(join_arg->cond_equal->current_level); - Item_equal *elem; - while ((elem= li++)) - { - and_args->push_back(elem, thd->mem_root); - } + ((Item_cond_and *) (join_arg->conds))->m_cond_equal= + *join_arg->cond_equal; + and_args->append((List<Item> *)&join_arg->cond_equal->current_level); } }