创建一个datetime表
> create table date_time(time datetime);> desc date_time;+-------+----------+------+-----+---------+-------+| Field | Type| Null | Key | Default | Extra |+-------+----------+------+-----+---------+-------+| time | datetime | YES || NULL | |+-------+----------+------+-----+---------+-------+
输入"10000-10-10 00:00:00"进行测试
> insert into date_time values("10000-10-10 00:00:00");ERROR 1292 (2): Incorrect datetime value: '10000-10-10 00:00:00' for column 'time' at row 1 # 报错
输入”23-01-02 12:23:56"测试
> insert into date_time values("23-01-02 12:23:56");> insert into date_time values("79-01-02 12:23:56");> select * from date_time;+---------------------+| time|+---------------------+| -01-02 12:23:56 || 1979-01-02 12:23:56 |+---------------------+
会和date一样，'00'-'69'会转换为2000-2069，'70'-'99'会转换为1970-1999
测试年份输入三位或者一位
> insert into date_time values("179-01-02 12:23:56");> insert into date_time values("9-01-02 12:23:56");> select * from date_time;+---------------------+| time|+---------------------+| -01-02 12:23:56 || 1979-01-02 12:23:56 || 0179-01-02 12:23:56 || 0009-01-02 12:23:56 |+---------------------+
可以存储进去，但会自动在前面补足0，使年份变为4位
输入年份格式为”00YY“
> insert into date_time values("0079-01-02 12:23:56");> select * from date_time;+---------------------+| time|+---------------------+| -01-02 12:23:56 || 1979-01-02 12:23:56 || 0179-01-02 12:23:56 || 0009-01-02 12:23:56 || 0079-01-02 12:23:56 | # 可以存储+---------------------+
最后测试极限时间
> insert into date_time values("0000-00-00 00:00:00");> insert into date_time values("9999-12-31 23:59:59");> select * from date_time;+---------------------+| time|+---------------------+| -01-02 12:23:56 || 1979-01-02 12:23:56 || 0179-01-02 12:23:56 || 0009-01-02 12:23:56 || 0079-01-02 12:23:56 || 0000-00-00 00:00:00 || 9999-12-31 23:59:59 |+---------------------+
总结：
datetime类型范围为”0000-00-00 00:00:00“~”9999-12-31 23:59:59“；要存储年份为两位数的需要在前面补足”00“，不然会按照date类型进行转换（'00'-'69'会转换为2000-2069，'70'-'99'会转换为1970-1999）；
