MySQL Date函數的正確用法

以下的文章主要介紹的是MySQL Date函數的實際應用其中包括如何獲取當前時間的具體操作,Unix時間的具體應用,時間前後、時間間隔與時間轉換的實際內容描述,以下就是文章的主要內容。
MySQL Date函數 1、獲取當前時間
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)  
MySQL Date函數 2、Unix時間
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)  
MySQL Date函數3、時間前後
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)  
 
MySQL Date函數4、時間間隔
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)  
MySQL Date函數5、時間轉換
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)