如何删除表数据,但不删除表列名?
ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------
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我必须删除表的所有内容,但不应删除表列名.
DELETE FROM table_name
WHERE [condition];
ID | NAME | AGE | ADDRESS | SALARY |
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小智 5
只是用
DELETE FROM table_name;
or
DELETE * FROM table_name;
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如果你还想添加条件
DELETE FROM table_name where 1 =1;
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小智 5
参考书目:
SQL - TRUNCATE TABLE 命令http://goo.gl/YN7N9Y
SQL - 语法http://goo.gl/viyYFU
SQLTRUNCATE TABLE命令用于从现有表中删除完整数据。
您还可以使用 DROP TABLE 命令删除完整的表,但它会从数据库中删除完整的表结构,如果您希望存储一些数据,则需要再次重新创建该表。
句法:
基本语法TRUNCATE TABLE如下:
TRUNCATE TABLE table_name;
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示例:考虑具有以下记录的 CUSTOMERS 表:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------+
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以下是截断的示例:
SQL > TRUNCATE TABLE CUSTOMERS;
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现在,CUSTOMERS 表被截断,以下是 SELECT 语句的输出:
SQL> SELECT * FROM CUSTOMERS;
Empty set (0.00 sec)
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