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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 Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
Warnings:
Note 1003 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 type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
drop table t1;
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