diff --git a/mysql-test/r/derived_opt.result b/mysql-test/r/derived_opt.result index 6e4ea1b5d36..0e8b49d5714 100644 --- a/mysql-test/r/derived_opt.result +++ b/mysql-test/r/derived_opt.result @@ -499,9 +499,42 @@ where D1.a= t1.a; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 10 Using where -1 PRIMARY hash_ALL key0 #hash#key0 5 test.t1.a 100 Using join buffer (flat, BNLH join) +1 PRIMARY ref key0 key0 5 test.t1.a 10 2 DERIVED t2 ALL NULL NULL NULL NULL 100 Using filesort set join_cache_level=@tmp_jcl; set optimizer_switch=@tmp_os; drop table t1, t2; +# +# Bug mdev-17382: equi-join of derived table with join_cache_level=4 +# +CREATE TABLE t1 ( +id int NOT NULL, +amount decimal DEFAULT NULL, +PRIMARY KEY (id) +); +CREATE TABLE t2 ( +id int NOT NULL, +name varchar(50) DEFAULT NULL, +PRIMARY KEY (id) +); +INSERT INTO t1 VALUES +(1, 10.0000), (2, 20.0000), (3, 30.0000), (4, 40.0000), +(5, NULL), (6, NULL), (7, 70.0000), (8, 80.0000); +INSERT INTO t2 VALUES +(1,'A'), (2,'B'), (3,'C'), (4,'D'), (5, NULL), (6, NULL), +(7,'E'), (8,'F'), (9,'G'), (10,'H'), (11, NULL), (12, NULL); +set join_cache_level=4; +EXPLAIN +SELECT t2.id,t2.name,t.total_amt +FROM t2 +LEFT JOIN +(SELECT id, sum(amount) total_amt FROM t1 GROUP BY id) AS t +ON t2.id=t.id +WHERE t2.id < 3; +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY t2 range PRIMARY PRIMARY 4 NULL 3 Using index condition +1 PRIMARY ref key0 key0 5 test.t2.id 2 +2 DERIVED t1 ALL NULL NULL NULL NULL 8 Using temporary; Using filesort +set join_cache_level=default; +DROP TABLE t1,t2; set optimizer_switch=@exit_optimizer_switch; diff --git a/mysql-test/r/innodb_mrr_cpk.result b/mysql-test/r/innodb_mrr_cpk.result index 28d7dd51df8..a2e43d7d127 100644 --- a/mysql-test/r/innodb_mrr_cpk.result +++ b/mysql-test/r/innodb_mrr_cpk.result @@ -226,7 +226,7 @@ set join_cache_level=3; explain SELECT 1 FROM (SELECT url, id FROM t2 LIMIT 1 OFFSET 20) derived RIGHT JOIN t1 ON t1.id = derived.id; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL # -1 PRIMARY hash_ALL key0 #hash#key0 25 test.t1.id # Using join buffer (flat, BNLH join) +1 PRIMARY ref key0 key0 25 test.t1.id # 2 DERIVED t2 ALL NULL NULL NULL NULL # set join_cache_level= @tmp_mdev5037; drop table t0,t1,t2; diff --git a/mysql-test/t/derived_opt.test b/mysql-test/t/derived_opt.test index 7f19553e4e5..aab95f69f26 100644 --- a/mysql-test/t/derived_opt.test +++ b/mysql-test/t/derived_opt.test @@ -363,5 +363,43 @@ set join_cache_level=@tmp_jcl; set optimizer_switch=@tmp_os; drop table t1, t2; +--echo # +--echo # Bug mdev-17382: equi-join of derived table with join_cache_level=4 +--echo # + +CREATE TABLE t1 ( + id int NOT NULL, + amount decimal DEFAULT NULL, +PRIMARY KEY (id) +); + +CREATE TABLE t2 ( + id int NOT NULL, + name varchar(50) DEFAULT NULL, +PRIMARY KEY (id) +); + +INSERT INTO t1 VALUES +(1, 10.0000), (2, 20.0000), (3, 30.0000), (4, 40.0000), +(5, NULL), (6, NULL), (7, 70.0000), (8, 80.0000); + +INSERT INTO t2 VALUES +(1,'A'), (2,'B'), (3,'C'), (4,'D'), (5, NULL), (6, NULL), +(7,'E'), (8,'F'), (9,'G'), (10,'H'), (11, NULL), (12, NULL); + +set join_cache_level=4; + +EXPLAIN +SELECT t2.id,t2.name,t.total_amt + FROM t2 + LEFT JOIN + (SELECT id, sum(amount) total_amt FROM t1 GROUP BY id) AS t + ON t2.id=t.id + WHERE t2.id < 3; + +set join_cache_level=default; + +DROP TABLE t1,t2; + # The following command must be the last one the file set optimizer_switch=@exit_optimizer_switch; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index a27053314bd..6f98bab32d3 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -11138,7 +11138,15 @@ uint check_join_cache_usage(JOIN_TAB *tab, effort now. */ if (tab->table->pos_in_table_list->is_materialized_derived()) + { no_bka_cache= true; + /* + Don't use hash join algorithm if the temporary table for the rows + of the derived table will be created with an equi-join key. + */ + if (tab->table->s->keys) + no_hashed_cache= true; + } /* Don't use join buffering if we're dictated not to by no_jbuf_after