drop table if exists t1,t2;
create table t1(str varchar(10) default 'def',strnull varchar(10),intg int default '10',rel double default '3.14');
insert into t1 values ('','',0,0.0);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
select default(str), default(strnull), default(intg), default(rel) from t1;
default(str)	default(strnull)	default(intg)	default(rel)
def	NULL	10	3.14
explain select default(str), default(strnull), default(intg), default(rel) from t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	1	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select default(`test`.`t1`.`str`) AS `default(str)`,default(`test`.`t1`.`strnull`) AS `default(strnull)`,default(`test`.`t1`.`intg`) AS `default(intg)`,default(`test`.`t1`.`rel`) AS `default(rel)` from `test`.`t1`
select * from t1 where str <> default(str);
str	strnull	intg	rel
		0	0
explain select * from t1 where str <> default(str);
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	1	100.00	Using where
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`str` AS `str`,`test`.`t1`.`strnull` AS `strnull`,`test`.`t1`.`intg` AS `intg`,`test`.`t1`.`rel` AS `rel` from `test`.`t1` where (`test`.`t1`.`str` <> <cache>(default(`test`.`t1`.`str`)))
drop table t1;
CREATE TABLE t1 (id int(11), s varchar(20));
Warnings:
Warning	1681	Integer display width is deprecated and will be removed in a future release.
INSERT INTO t1 VALUES (1, 'one'), (2, 'two'), (3, 'three');
SELECT s, 32 AS mi FROM t1 GROUP BY s HAVING DEFAULT(mi) IS NULL;
ERROR HY000: Field 'mi' doesn't have a default value
DROP TABLE t1;