在sql中对时间的操作有很多方法,我们这里总结了几种方法,像我自己做数据库时会把日期字段设置为int(10)这来保存日期的unix_timestamp,最后再加减比较也方便很多,因为我们用的时整型比较哦,有需要的朋友可以自己选择下面任何一种方法。
最简单的用date_format函数进行比较
代码如下 | 复制代码 |
* from tb where c> date_format('2007-07-06','%Y%m%d') and c
|
STATDAY是形如2006031001的日期数据字段
代码如下 | 复制代码 |
select * from LOGINSTAT where STATDAY> date_format(curdate()-1,'%Y%m%d') and STATDAY >= date_format(curdate(),'%Y%m%d'); |
或者:
代码如下 | 复制代码 |
select * from LOGINSTAT where STATDAY> date_format(curdate()-1,'%Y%m%d%H') and STATDAY >= date_format(curdate(),'%Y%m%d%H'); |
其他用法:
代码如下 | 复制代码 |
select * from LOGINSTAT where STATDAY >= date_format('$date1','%Y%m%d%H') and STATDAY |
中存的时间格式为2008-12-28 18:08:08,现在先要从一个一个结果集rs中获得一个日期时间。我先用rs.getDate()方法试着获取时间,结果只有年月日,无法获取小时、分和秒。最后解决的方法是:
代码如下 | 复制代码 |
Date time1=new Date(rs.getTimestamp("pub_time").getTime()); |
获得的pubtime为String型,在sql语句中用mysql的时间函数date_format('time','format')转换:
代码如下 | 复制代码 |
String sqlstr="select * from do_document where pub_time |
然后执行该sql语句就查到了满足条件的记录。
分享三
1。
代码如下 | 复制代码 |
SELECT * FROM 表名 WHERE 字段名 BETWEEN 'YYYY-MM-1' AND 'YYYY-MM-30'; |
可以用日期时间函数进一步修正给出的日期
datetime和date型的数据可以直接比较,比较时datetime型的数据自动转换成date型数据.
2。函数
代码如下 | 复制代码 |
select * |
我自己常用的是下面的方法
MySQL的UNIX_TIMESTAMP函?悼梢?б?????br /> 比如
代码如下 | 复制代码 |
UNIX_TIMESTAMP('2008-08-08 20:08:08'); |
返回值是整?担?梢灾苯蛹?p
实例
代码如下 | 复制代码 |
select * from table where createtime>unix_timestamp('2011-1-1 12:12:12'); |

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