create table t1 (d date);
insert into t1 values ('2012-00-00');
select * from t1;
d
2012-00-00
update t1 set d = adddate(d, interval 1 day);
Warnings:
Warning	1292	Incorrect datetime value: '2012-00-00'
select * from t1;
d
NULL
drop table t1;