DELETE 語句用于刪除表中的記錄。
SQL DELETE 語句
DELETE 語句用于刪除表中的行。
SQL DELETE 語法
DELETE FROM table_name
WHERE some_column=some_value;
WHERE some_column=some_value;
![]() | 請注意 SQL DELETE 語句中的 WHERE 子句! WHERE 子句規(guī)定哪條記錄或者哪些記錄需要刪除。如果您省略了 WHERE 子句,所有的記錄都將被刪除! |
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演示數(shù)據(jù)庫
在本教程中,我們將使用 php 樣本數(shù)據(jù)庫。
下面是選自 "Websites" 表的數(shù)據(jù):
+----+--------------+---------------------------+-------+---------+
| id | name | url | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1 | Google | https://www.google.cm/ | 1 | USA |
| 2 | 淘寶 | https://www.taobao.com/ | 13 | CN |
| 3 | php中文網(wǎng) | http://miracleart.cn/ | 4689 | CN |
| 4 | 微博 | http://weibo.com/ | 20 | CN |
| 5 | Facebook | https://www.facebook.com/ | 3 | USA |
| 6 | 百度 | https://www.baidu.com/ | 4 | CN |
| 7 | stackoverflow | http://stackoverflow.com/ | 0 | IND |
+----+---------------+---------------------------+-------+---------+
| id | name | url | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1 | Google | https://www.google.cm/ | 1 | USA |
| 2 | 淘寶 | https://www.taobao.com/ | 13 | CN |
| 3 | php中文網(wǎng) | http://miracleart.cn/ | 4689 | CN |
| 4 | 微博 | http://weibo.com/ | 20 | CN |
| 5 | Facebook | https://www.facebook.com/ | 3 | USA |
| 6 | 百度 | https://www.baidu.com/ | 4 | CN |
| 7 | stackoverflow | http://stackoverflow.com/ | 0 | IND |
+----+---------------+---------------------------+-------+---------+
SQL DELETE 實(shí)例
假設(shè)我們要從 "Websites" 表中刪除網(wǎng)站名為 "百度" 且國家為 CN 的網(wǎng)站 。
我們使用下面的 SQL 語句:
實(shí)例
DELETE FROM Websites
WHERE name='百度' AND country='CN';
WHERE name='百度' AND country='CN';
執(zhí)行以上 SQL,再讀取 "Websites" 表,數(shù)據(jù)如下所示:

刪除所有數(shù)據(jù)
您可以在不刪除表的情況下,刪除表中所有的行。這意味著表結(jié)構(gòu)、屬性、索引將保持不變:
DELETE FROM table_name;
or
DELETE * FROM table_name;
or
DELETE * FROM table_name;
注釋:在刪除記錄時(shí)要格外小心!因?yàn)槟荒苤貋恚?/p>