mysql如何获取系统时间？

hantsy

mysql> select current_date;//今天
+----------------+
| current_date() |
+----------------+
| 2004-04-07     |
+----------------+
1 row in set (0.00 sec)

mysql> select current_date()-1;//昨天
+------------------+
| current_date()-1 |
+------------------+
|         20040406 |
+------------------+
1 row in set (0.02 sec)

mysql> select sysdate();
+---------------------+
| sysdate()           |
+---------------------+
| 2004-04-07 10:46:45 |
+---------------------+
1 row in set (0.00 sec)