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drop table if exists t1;
set @@session.sql_auto_is_null=1;
select {fn length("hello")}, { date "1997-10-20" };
{fn length("hello")} 1997-10-20
5 1997-10-20
create table t1 (a int not null auto_increment,b int not null,primary key (a,b));
insert into t1 SET A=NULL,B=1;
insert into t1 SET a=null,b=2;
select * from t1 where a is null and b=2;
a b
select * from t1 where a is null;
a b
2 2
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
explain select * from t1 where b is null;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where false
drop table t1;
CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
INSERT INTO t1 VALUES (NULL);
SELECT a, last_insert_id() FROM t1 WHERE a IS NULL;
a last_insert_id()
1 1
SELECT a, last_insert_id() FROM t1 WHERE a IS NULL;
a last_insert_id()
1 1
SELECT a, last_insert_id() FROM t1;
a last_insert_id()
1 1
DROP TABLE t1;
#
# Bug#29171668: ODBC SUBSTITUTION FOR LAST_INSERT_ID() TRIGGERS
# A NON-DETERMINISTIC TRANSFORMATION
#
CREATE TABLE t1(a BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY);
CREATE TABLE t2(b INT);
INSERT INTO t2 VALUES (2),(3),(4);
INSERT INTO t1 VALUES ();
SELECT * FROM t2 LEFT JOIN t1 ON a=b WHERE a IS NULL;
b a
2 NULL
3 NULL
4 NULL
INSERT INTO t1 VALUES ();
SELECT * FROM t2 LEFT JOIN t1 ON a=b WHERE a IS NULL;
b a
3 NULL
4 NULL
INSERT INTO t1 VALUES ();
SELECT * FROM t1 HAVING a IS NULL;
a
SELECT a, a IS NULL FROM t1 WHERE a IS NULL;
a a IS NULL
3 0
SELECT * FROM t1 WHERE a IS NULL;
a
3
SELECT * FROM t1 WHERE a IS NULL;
a
3
INSERT INTO t1 VALUES (9223372036854775807);
INSERT INTO t1 VALUES ();
SELECT * FROM t1 WHERE a IS NULL;
a
9223372036854775808
DROP TABLE t1, t2;
set @@session.sql_auto_is_null=default;
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