drop table if exists t1; SET SQL_SAFE_UPDATES=1,SQL_SELECT_LIMIT=4, MAX_JOIN_SIZE=8; create table t1 (a int auto_increment primary key, b char(20)) charset utf8mb4; insert into t1 values(1,"test"); SELECT SQL_BUFFER_RESULT * from t1; a b 1 test update t1 set b="a" where a=1; delete from t1 where a=1; insert into t1 values(1,"test"),(2,"test2"); SELECT SQL_BUFFER_RESULT * from t1; a b 1 test 2 test2 update t1 set b="a" where a=1; select 1 from t1,t1 as t2,t1 as t3; 1 1 1 1 1 update t1 set b="a"; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. update t1 set b="a" where b="test"; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. delete from t1; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. delete from t1 where b="test"; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. delete from t1 where a+0=1; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. select 1 from t1,t1 as t2,t1 as t3,t1 as t4,t1 as t5; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay update t1 set b="a" limit 1; update t1 set b="a" where b="b" limit 2; delete from t1 where b="test" limit 1; delete from t1 where a+0=1 limit 2; alter table t1 add key b (b); SET MAX_JOIN_SIZE=1; SELECT @@MAX_JOIN_SIZE, @@SQL_BIG_SELECTS; @@MAX_JOIN_SIZE @@SQL_BIG_SELECTS 1 0 insert into t1 values (null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"); SELECT * from t1 order by a; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay SET SQL_BIG_SELECTS=1; SELECT * from t1 order by a; a b 2 test2 3 a 4 a 5 a SET MAX_JOIN_SIZE=1; SELECT * from t1; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay SET MAX_JOIN_SIZE=DEFAULT; SELECT * from t1; a b 2 test2 3 a 4 a 5 a analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status OK insert into t1 values (null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"); explain select STRAIGHT_JOIN * from t1,t1 as t2 where t1.b=t2.b; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 NULL ALL b NULL NULL NULL 21 100.00 Using where 1 SIMPLE t2 NULL ref b b 81 test.t1.b 6 100.00 NULL Warnings: Note 1003 /* select#1 */ select straight_join `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` join `test`.`t1` `t2` where (`test`.`t2`.`b` = `test`.`t1`.`b`) set MAX_SEEKS_FOR_KEY=1; explain select STRAIGHT_JOIN * from t1,t1 as t2 where t1.b=t2.b; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 NULL ALL b NULL NULL NULL 21 100.00 Using where 1 SIMPLE t2 NULL ref b b 81 test.t1.b 6 100.00 NULL Warnings: Note 1003 /* select#1 */ select straight_join `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` join `test`.`t1` `t2` where (`test`.`t2`.`b` = `test`.`t1`.`b`) SET MAX_SEEKS_FOR_KEY=DEFAULT; drop table t1; create table t1 (a int); insert into t1 values (1),(2),(3),(4),(5); insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; set local max_join_size=4; select * from (select * from t1) x; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay set local max_join_size=1; select * from (select a.a as aa, b.a as ba from t1 a, t1 b) x; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay set local max_join_size=1; select * from (select 1 union select 2 union select 3) x; ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay drop table t1; SET SQL_SAFE_UPDATES=0,SQL_SELECT_LIMIT=DEFAULT, MAX_JOIN_SIZE=DEFAULT; # # Bug #28145710: SQL_SAFE_UPDATES ERROR IS INSUFFICIENTLY INFORMATIVE # CREATE TABLE t1 (c1 INT NOT NULL, c2 VARCHAR(200) NOT NULL, UNIQUE KEY idx1 (c1), UNIQUE KEY idx2 (c2)); CREATE TABLE t2 (c1 INT NOT NULL, c2 VARCHAR(200) NOT NULL, UNIQUE KEY idx1 (c1)); INSERT INTO t1 VALUES (1, 'a'), (2, 'b'), (3, 'c'), (4, 'd'); INSERT INTO t2 VALUES (11, 'a'), (12, 'b'), (3, 'c'), (14, 'd'); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status OK test.t2 analyze status OK SET SESSION sql_safe_updates=1; SET RANGE_OPTIMIZER_MAX_MEM_SIZE= 1; EXPLAIN DELETE FROM t1 WHERE c1 IN (1,22); id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 DELETE t1 NULL ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Warning 3170 Memory capacity of 1 bytes for 'range_optimizer_max_mem_size' exceeded. Range optimization was not done for this query. Note 1003 delete from `test`.`t1` where (`test`.`t1`.`c1` in (1,22)) DELETE FROM t1 WHERE c1 IN (1,22); ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Memory capacity of 1 bytes for 'range_optimizer_max_mem_size' exceeded. Range optimization was not done for this query. EXPLAIN UPDATE t1 SET c1=20 WHERE c1 IN (1,22); id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 UPDATE t1 NULL ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Warning 3170 Memory capacity of 1 bytes for 'range_optimizer_max_mem_size' exceeded. Range optimization was not done for this query. Note 1003 update `test`.`t1` set `test`.`t1`.`c1` = 20 where (`test`.`t1`.`c1` in (1,22)) UPDATE t1 SET c1=20 WHERE c1 IN (1,22); ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Memory capacity of 1 bytes for 'range_optimizer_max_mem_size' exceeded. Range optimization was not done for this query. SET RANGE_OPTIMIZER_MAX_MEM_SIZE= default; EXPLAIN DELETE t1 FROM t1 JOIN t2 ON t1.c2 = t2.c1; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 DELETE t1 NULL ALL idx2 NULL NULL NULL 4 100.00 NULL 1 SIMPLE t2 NULL eq_ref idx1 idx1 4 test.t1.c2 1 100.00 Using where; Using index Warnings: Warning 1739 Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' Note 1003 delete `test`.`t1` from `test`.`t1` join `test`.`t2` where (`test`.`t1`.`c2` = `test`.`t2`.`c1`) DELETE t1 FROM t1 JOIN t2 ON t1.c2 = t2.c1; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' EXPLAIN UPDATE t1, t2 SET t1.c1=20 WHERE t1.c2 = t2.c1; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 UPDATE t1 NULL ALL idx2 NULL NULL NULL 4 100.00 NULL 1 SIMPLE t2 NULL eq_ref idx1 idx1 4 test.t1.c2 1 100.00 Using where; Using index Warnings: Warning 1739 Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' Note 1003 update `test`.`t1` join `test`.`t2` set `test`.`t1`.`c1` = 20 where (`test`.`t1`.`c2` = `test`.`t2`.`c1`) UPDATE t1, t2 SET t1.c1=20 WHERE t1.c2 = t2.c1; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' EXPLAIN DELETE t2 FROM t1 JOIN t2 ON t1.c2 = t2.c1; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 NULL index idx2 idx2 802 NULL 4 100.00 Using index 1 DELETE t2 NULL eq_ref idx1 idx1 4 test.t1.c2 1 100.00 Using where Warnings: Warning 1739 Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' Note 1003 delete `test`.`t2` from `test`.`t1` join `test`.`t2` where (`test`.`t1`.`c2` = `test`.`t2`.`c1`) DELETE t2 FROM t1 JOIN t2 ON t1.c2 = t2.c1; Warnings: Warning 1739 Cannot use ref access on index 'idx2' due to type or collation conversion on field 'c2' EXPLAIN DELETE FROM t1 WHERE c2 IN(1,2222); id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 DELETE t1 NULL ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Warning 1739 Cannot use range access on index 'idx2' due to type or collation conversion on field 'c2' Note 1003 delete from `test`.`t1` where (`test`.`t1`.`c2` in (1,2222)) DELETE FROM t1 WHERE c2 IN(1,2222); ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Cannot use range access on index 'idx2' due to type or collation conversion on field 'c2' EXPLAIN UPDATE t1 SET c1=20 WHERE c2 IN(1,2222); id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 UPDATE t1 NULL ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Warning 1739 Cannot use range access on index 'idx2' due to type or collation conversion on field 'c2' Note 1003 update `test`.`t1` set `test`.`t1`.`c1` = 20 where (`test`.`t1`.`c2` in (1,2222)) UPDATE t1 SET c1=20 WHERE c2 IN(1,2222); ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. Cannot use range access on index 'idx2' due to type or collation conversion on field 'c2' EXPLAIN DELETE FROM t2 WHERE c2 IN('a','e'); id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 DELETE t2 NULL ALL NULL NULL NULL NULL 4 100.00 Using where Warnings: Note 1003 delete from `test`.`t2` where (`test`.`t2`.`c2` in ('a','e')) DELETE FROM t2 WHERE c2 IN('a','e'); ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. EXPLAIN DELETE FROM t2; id select_type table partitions type possible_keys key key_len ref rows filtered Extra 1 DELETE t2 NULL ALL NULL NULL NULL NULL 4 100.00 # Warnings: Note 1003 delete from `test`.`t2` DELETE FROM t2; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. SET sql_log_bin= 0; DELETE FROM t2; ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. SET sql_log_bin= default; DROP TABLE t1, t2; SET SESSION sql_safe_updates=default;