帮忙看看这个简单的SQL!
表table1有如下一批数据:
qsb3 qsb7
2004-11-17 09:17:00 2004-11-17 11:12:00
2004-11-17 07:21:00 2004-11-17 12:17:00
2004-11-17 11:17:00 2004-11-17 00:00:00
我用以下两种SQL 怎么结果不一样:
1. select * from table1 where left(qsb3,10)=left(qsb7,10)(显示结果为正常)
2. select * from qzj1
where year(qsb3)=year(qsb7) and month(qsb3)=year(qsb7) and day(qsb3)=day(qsb7)(结果为零)