mysql基础:mysql列类型--时间和日期_MySQL
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mysql基础:mysql列类型--时间和日期
DATE
日期。支持的范围为'1000-01-01'到'9999-12-31'。MySQL以'YYYY-MM-DD'格式显示DATE值,但允许使用字符串或数字为DATE列分配值。
· DATETIME
日期和时间的组合。支持的范围是'1000-01-01 00:00:00'到'9999-12-31 23:59:59'。MySQL以'YYYY-MM-DD HH:MM:SS'格式显示DATETIME值,但允许使用字符串或数字为DATETIME列分配值。
· TIMESTAMP[(M)]
时间戳。范围是'1970-01-01 00:00:00'到2037年。
TIMESTAMP列用于INSERT或UPDATE操作时记录日期和时间。如果你不分配一个值,表中的第一个TIMESTAMP列自动设置为最近操作的日期和时间。也可以通过分配一个NULL值,将TIMESTAMP列设置为当前的日期和时间。
TIMESTAMP值返回后显示为'YYYY-MM-DD HH:MM:SS'格式的字符串,显示宽度固定为19个字符。如果想要获得数字值,应在TIMESTAMP 列添加+0。
注释:MySQL 4.1以前使用的TIMESTAMP格式在MySQL 5.1中不支持;关于旧格式的信息参见MySQL 4.1 参考手册。
· TIME
时间。范围是'-838:59:59'到'838:59:59'。MySQL以'HH:MM:SS'格式显示TIME值,但允许使用字符串或数字为TIME列分配值。
· YEAR[(2|4)]
两位或四位格式的年。默认是四位格式。在四位格式中,允许的值是1901到2155和0000。在两位格式中,允许的值是70到69,表示从1970年到2069年。MySQL以YYYY 格式显示YEAR值,但允许使用字符串或数字为YEAR列分配值。

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