MySql Date函数
1、获取当前时间
mysql> select current_timestamp();
+———————+
| current_timestamp() |
+———————+
| 2010-01-18 21:24:37 |
+———————+
1 row in set (0.00 sec)
mysql> select current_date();
+—————-+
| current_date() |
+—————-+
| 2010-01-18 |
+—————-+
1 row in set (0.00 sec)
mysql> select current_time();
+—————-+
| current_time() |
+—————-+
| 21:24:46 |
+—————-+
1 row in set (0.00 sec)
2、Unix时间
mysql> select unix_timestamp();
+——————+
| unix_timestamp() |
+——————+
| 1263821184 |
+——————+
1 row in set (0.00 sec)
mysql> select from_unixtime(1263821182);
+—————————+
| from_unixtime(1263821182) |
+—————————+
| 2010-01-18 21:26:22 |
+—————————+
1 row in set (0.00 sec)
3、时间前后
mysql> select date_add(current_timestamp, interval 1 day);
+———————————————+
| date_add(current_timestamp, interval 1 day) |
+———————————————+
| 2010-01-19 21:27:53 |
+———————————————+
1 row in set (0.00 sec)
mysql> select date_add(current_time, interval 1 day);
+—————————————-+
| date_add(current_time, interval 1 day) |
+—————————————-+
| NULL |
+—————————————-+
1 row in set, 1 warning (0.00 sec)
mysql> select date_add(current_date, interval 1 day);
+—————————————-+
| date_add(current_date, interval 1 day) |
+—————————————-+
| 2010-01-19 |
+—————————————-+
1 row in set (0.00 sec)
mysql> select date_sub(current_timestamp, interval 1 day);
+———————————————+
| date_sub(current_timestamp, interval 1 day) |
+———————————————+
| 2010-01-17 21:28:41 |
+———————————————+
1 row in set (0.00 sec)
mysql> select date_sub(current_date, interval 1 day);
+—————————————-+
| date_sub(current_date, interval 1 day) |
+—————————————-+
| 2010-01-17 |
+—————————————-+
1 row in set (0.00 sec)
mysql> select date_sub(current_time, interval 1 day);
+—————————————-+
| date_sub(current_time, interval 1 day) |
+—————————————-+
| NULL |
+—————————————-+
1 row in set, 1 warning (0.00 sec)
4、时间间隔
mysql> select datediff(’2010-01-18′,’2010-01-17′);
+————————————-+
| datediff(’2010-01-18′,’2010-01-17′) |
+————————————-+
| 1 |
+————————————-+
1 row in set (0.00 sec)
mysql> select timediff(’2010-01-18 12:00′,’2010-01-17 11:00′);
+————————————————-+
| timediff(’2010-01-18 12:00′,’2010-01-17 11:00′) |
+————————————————-+
| 25:00:00 |
+————————————————-+
1 row in set (0.00 sec)
5、时间转换
mysql> select time_to_sec(’25:00:00′);
+————————-+
| time_to_sec(’25:00:00′) |
+————————-+
| 90000 |
+————————-+
1 row in set (0.00 sec)
mysql> select sec_to_time(90000);
+——————–+
| sec_to_time(90000) |
+——————–+
| 25:00:00 |
+——————–+
1 row in set (0.00 sec)