怎么查每个月的第一天

Question

2010-1-1
2010-2-1

Answer 1

select *
from tb 
where day(timeCol) = 1

Answer 2

@输入一个日期-interval DAYOFMONTH(@输入一个日期)-1 day

Answer 3

mysql> select curdate()-interval DAYOFMONTH(curdate())-1 day;
+------------------------------------------------+
| curdate()-interval DAYOFMONTH(curdate())-1 day |
+------------------------------------------------+
| 2010-08-01                                     |
+------------------------------------------------+
1 row in set (0.14 sec)mysql>