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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);
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 extended select default(str), default(strnull), default(intg), default(rel) from t1;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1 100.00
Warnings:
Note 1003 select default('') AS `default(str)`,default('') AS `default(strnull)`,default(0) AS `default(intg)`,default(0) AS `default(rel)` from dual
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 type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
drop table t1;
CREATE TABLE t1 (id int(11), s varchar(20));
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;
set timestamp=unix_timestamp('2001-01-01 10:20:30.123456');
create table t1 (a int default 1, b int default (a+1),
c varchar(100) default 'foo', d text default 'bar',
e timestamp default now(), f timestamp(6) default now(2));
insert t1 () values ();
insert t1 (a) values (10);
select default(a),default(b),default(c),default(d),default(e),default(f) from t1;
default(a) default(b) default(c) default(d) default(e) default(f)
1 2 foo bar 2001-01-01 10:20:30 2001-01-01 10:20:30.120000
1 11 foo bar 2001-01-01 10:20:30 2001-01-01 10:20:30.120000
drop table t1;
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