# # Test of different EXPLAINs --disable_warnings drop table if exists t1; --enable_warnings create table t1 (id int not null, str char(10), unique(str)); explain select * from t1; insert into t1 values (1, null),(2, null),(3, "foo"),(4, "bar"); select * from t1 where str is null; select * from t1 where str="foo"; explain select * from t1 where str is null; explain select * from t1 where str="foo"; explain select * from t1 ignore key (str) where str="foo"; explain select * from t1 use key (str,str) where str="foo"; #The following should give errors --error 1176 explain select * from t1 use key (str,str,foo) where str="foo"; --error 1176 explain select * from t1 ignore key (str,str,foo) where str="foo"; drop table t1; explain select 1; create table t1 (a int not null); explain select count(*) from t1; insert into t1 values(1); explain select count(*) from t1; insert into t1 values(1); explain select count(*) from t1; drop table t1; # # Bug #3403 Wrong encoding in EXPLAIN SELECT output # set names koi8r; create table таб (кол0 int, кол1 int, key инд0 (кол0), key инд01 (кол0,кол1)); insert into таб (кол0) values (1); insert into таб (кол0) values (2); explain select кол0 from таб where кол0=1; drop table таб; set names latin1; # End of 4.1 tests # # Bug#15463: EXPLAIN SELECT..INTO hangs the client (QB, command line) # select 3 into @v1; explain select 3 into @v1; # # Bug#22331: Wrong WHERE in EXPLAIN EXTENDED when all expressions were # optimized away. # create table t1(f1 int, f2 int); insert into t1 values (1,1); create view v1 as select * from t1 where f1=1; explain extended select * from v1 where f2=1; explain extended select * from t1 where 0; explain extended select * from t1 where 1; explain extended select * from t1 having 0; explain extended select * from t1 having 1; drop view v1; drop table t1; # # Bug #32241: memory corruption due to large index map in 'Range checked for # each record' # CREATE TABLE t1(c INT); INSERT INTO t1 VALUES (),(); CREATE TABLE t2 (b INT, KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b), KEY(b),KEY(b),KEY(b),KEY(b),KEY(b)); INSERT INTO t2 VALUES (),(),(); # We only need to make sure that there is no buffer overrun and the index map # is displayed correctly --replace_column 1 X 2 X 3 X 4 X 5 X 6 X 7 X 8 X 9 X EXPLAIN SELECT 1 FROM (SELECT 1 FROM t2,t1 WHERE b < c GROUP BY 1 LIMIT 1) AS d2; DROP TABLE t2; DROP TABLE t1; # # Bug #34773: query with explain extended and derived table / other table # crashes server # CREATE TABLE t1(a INT); CREATE TABLE t2(a INT); INSERT INTO t1 VALUES (1),(2); INSERT INTO t2 VALUES (1),(2); EXPLAIN EXTENDED SELECT 1 FROM (SELECT COUNT(DISTINCT t1.a) FROM t1,t2 GROUP BY t1.a) AS s1; EXPLAIN EXTENDED SELECT 1 FROM (SELECT COUNT(DISTINCT t1.a) FROM t1,t2 GROUP BY t1.a) AS s1; prepare s1 from 'EXPLAIN EXTENDED SELECT 1 FROM (SELECT COUNT(DISTINCT t1.a) FROM t1,t2 GROUP BY t1.a) AS s1'; execute s1; prepare s1 from 'EXPLAIN EXTENDED SELECT 1 FROM (SELECT COUNT(DISTINCT t1.a) FROM t1,t2 GROUP BY t1.a) AS s1'; execute s1; execute s1; DROP TABLE t1,t2; # # Bug #43354: Use key hint can crash server in explain extended query # CREATE TABLE t1 (a INT PRIMARY KEY); --error ER_KEY_DOES_NOT_EXISTS EXPLAIN EXTENDED SELECT COUNT(a) FROM t1 USE KEY(a); DROP TABLE t1; # # Bug#45989 memory leak after explain encounters an error in the query # CREATE TABLE t1(a LONGTEXT); INSERT INTO t1 VALUES (repeat('a',@@global.max_allowed_packet)); INSERT INTO t1 VALUES (repeat('b',@@global.max_allowed_packet)); --error ER_BAD_FIELD_ERROR EXPLAIN SELECT DISTINCT 1 FROM t1, (SELECT DISTINCTROW a AS away FROM t1 GROUP BY a WITH ROLLUP) as d1 WHERE t1.a = d1.a; DROP TABLE t1; --echo # --echo # Bug#48295: --echo # explain extended crash with subquery and ONLY_FULL_GROUP_BY sql_mode --echo # CREATE TABLE t1 (f1 INT not null); SELECT @@session.sql_mode INTO @old_sql_mode; SET SESSION sql_mode='ONLY_FULL_GROUP_BY'; # EXPLAIN EXTENDED (with subselect). used to crash. should give NOTICE. # Before moving max/min optimization to optimize phase this statement # generated error, but as far as original query do not contain aggregate # function user should not see error # --error ER_MIX_OF_GROUP_FUNC_AND_FIELDS EXPLAIN EXTENDED SELECT 1 FROM t1 WHERE f1 > ALL( SELECT t.f1 FROM t1,t1 AS t ); SET SESSION sql_mode=@old_sql_mode; DROP TABLE t1; --echo End of 5.0 tests. --echo # --echo # Bug#37870: Usage of uninitialized value caused failed assertion. --echo # create table t1 (dt datetime not null, t time not null); create table t2 (dt datetime not null); insert into t1 values ('2001-01-01 1:1:1', '1:1:1'), ('2001-01-01 1:1:1', '1:1:1'); insert into t2 values ('2001-01-01 1:1:1'), ('2001-01-01 1:1:1'); SET @save_join_cache_level=@@join_cache_level; SET join_cache_level=0; flush tables; EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL ); flush tables; SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL ); flush tables; EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' ); flush tables; SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' ); SET join_cache_level=@save_join_cache_level; drop tables t1, t2; --echo # --echo # Bug#47669: Query showed by EXPLAIN EXTENDED gives different result from original query --echo # CREATE TABLE t1 (c int); INSERT INTO t1 VALUES (NULL); CREATE TABLE t2 (d int); INSERT INTO t2 VALUES (NULL), (0); EXPLAIN EXTENDED SELECT (SELECT 1 FROM t2 WHERE d = c) FROM t1; DROP TABLE t1, t2; --echo # --echo # Bug#30302: Tables that were optimized away are printed in the --echo # EXPLAIN EXTENDED warning. --echo # create table t1(f1 int); create table t2(f2 int); insert into t1 values(1); insert into t2 values(1),(2); explain extended select * from t1 where f1=1; explain extended select * from t1 join t2 on f1=f2 where f1=1; drop table t1,t2; --echo # --echo # Bug #48419: another explain crash.. --echo # CREATE TABLE t1 (a INT); CREATE TABLE t2 (b BLOB, KEY b(b(100))); INSERT INTO t2 VALUES ('1'), ('2'), ('3'); FLUSH TABLES; EXPLAIN SELECT 1 FROM t1 WHERE a = (SELECT 1 FROM t1 t JOIN t2 WHERE b <= 1 AND t.a); DROP TABLE t1, t2; --echo # --echo # Bug #48573: difference of index selection between rpm binary and --echo # .tar.gz, windows vs linux.. --echo # CREATE TABLE t1(c1 INT, c2 INT, c4 INT, c5 INT, KEY(c2, c5), KEY(c2, c4, c5)); INSERT INTO t1 VALUES(4, 1, 1, 1); INSERT INTO t1 VALUES(3, 1, 1, 1); INSERT INTO t1 VALUES(2, 1, 1, 1); INSERT INTO t1 VALUES(1, 1, 1, 1); INSERT INTO t1 VALUES(5, 2, 1, 1); INSERT INTO t1 VALUES(6, 2, 1, 1); INSERT INTO t1 VALUES(7, 3, 1, 1); INSERT INTO t1 VALUES(9, 3, 1, 1); INSERT INTO t1 VALUES(10, 4, 1, 1); INSERT INTO t1 VALUES(11, 4, 1, 1); EXPLAIN SELECT c1 FROM t1 WHERE c2 = 1 AND c4 = 1 AND c5 = 1; DROP TABLE t1; --echo # --echo # Bug#56814 Explain + subselect + fulltext crashes server --echo # CREATE TABLE t1(f1 VARCHAR(6) NOT NULL, FULLTEXT KEY(f1),UNIQUE(f1)); INSERT INTO t1 VALUES ('test'); EXPLAIN SELECT 1 FROM t1 WHERE 1 > ALL((SELECT t1.f1 FROM t1 JOIN t1 a ON (MATCH(t1.f1) AGAINST ("")) WHERE t1.f1 GROUP BY t1.f1)); PREPARE stmt FROM 'EXPLAIN SELECT 1 FROM t1 WHERE 1 > ALL((SELECT t1.f1 FROM t1 RIGHT OUTER JOIN t1 a ON (MATCH(t1.f1) AGAINST ("")) WHERE t1.f1 GROUP BY t1.f1))'; EXECUTE stmt; EXECUTE stmt; DEALLOCATE PREPARE stmt; PREPARE stmt FROM 'EXPLAIN SELECT 1 FROM t1 WHERE 1 > ALL((SELECT t1.f1 FROM t1 JOIN t1 a ON (MATCH(t1.f1) AGAINST ("")) WHERE t1.f1 GROUP BY t1.f1))'; EXECUTE stmt; EXECUTE stmt; DEALLOCATE PREPARE stmt; DROP TABLE t1; --echo End of 5.1 tests. --echo # --echo # Bug#11829785 EXPLAIN EXTENDED CRASH WITH RIGHT OUTER JOIN, SUBQUERIES --echo # CREATE TABLE t1(a INT); INSERT INTO t1 VALUES (0), (0); PREPARE s FROM 'EXPLAIN EXTENDED SELECT SUBSTRING(1, (SELECT 1 FROM t1 a1 RIGHT OUTER JOIN t1 ON 0)) AS d FROM t1 WHERE 0 > ANY (SELECT @a FROM t1)'; --error ER_SUBQUERY_NO_1_ROW EXECUTE s; DEALLOCATE PREPARE s; DROP TABLE t1; --echo # --echo # Bug#776295: EXPLAIN EXTENDED with always false multiple equality --echo # in the WHERE condition of a derived table --echo # CREATE TABLE t1 (a int) ; CREATE TABLE t2 (a int) ; INSERT INTO t2 VALUES (8); set @tmp_optimizer_switch=@@optimizer_switch; set optimizer_switch='derived_merge=off,derived_with_keys=off'; EXPLAIN EXTENDED SELECT * FROM ( SELECT t1.a FROM t1,t2 WHERE t2.a = t1.a ) AS t; set optimizer_switch=@tmp_optimizer_switch; DROP TABLE t1,t2; --echo # --echo # MDEV-7215: EXPLAIN REPLACE produces an error: --echo # Column count doesn't match value count --echo # create table t1 (a int); insert into t1 values (1); create table t2 (b int, c int); replace into t2 select 100, (select a from t1); explain replace into t2 select 100, (select a from t1); #analyze replace into t2 select 100, (select a from t1); drop table t1, t2; --echo # End of 10.1 tests --echo # --echo # End of 10.2 test --echo # --echo # --echo # MDEV-25564: Server crashed on running some EXPLAIN statements --echo # EXPLAIN (SELECT 1,3) UNION (SELECT 2,1) ORDER BY (SELECT 2); --echo # --echo # MDEV-23160: SIGSEGV in Explain_node::print_explain_for_children on UNION SELECT --echo # CREATE TABLE t1 (a INT); INSERT INTO t1 VALUES (1),(2),(3); EXPLAIN SELECT * FROM t1 WHERE a IN (SELECT a FROM t1 UNION SELECT a FROM t1 ORDER BY (SELECT a)) UNION SELECT * FROM t1 ORDER BY (SELECT a); drop table t1; --disable_ps_protocol explain VALUES ( (VALUES (2))) UNION VALUES ( (SELECT 3)); --enable_ps_protocol