T Sql 简明教程
T-SQL - UPDATE Statement
SQL Server UPDATE 查询用于修改表中现有的记录。
The SQL Server UPDATE Query is used to modify the existing records in a table.
可以将 WHERE 子句与 UPDATE 查询结合使用以更新所选行，否则会影响所有行。
You can use WHERE clause with UPDATE query to update selected rows otherwise all the rows would be affected.
Syntax
以下是带 WHERE 子句的 UPDATE 查询的基本语法：
Following is the basic syntax of UPDATE query with WHERE clause −
UPDATE table_name
SET column1 = value1, column2 = value2...., columnN = valueN
WHERE [condition];可以使用 AND 或 OR 运算符组合 N 个条件。
You can combine N number of conditions using AND or OR operators.
Example
考虑包含以下记录的 CUSTOMERS 表：
Consider the CUSTOMERS table having the following records −
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以下命令是一个示例，用于更新 ID 为 6 的客户地址：
Following command is an example, which would update ADDRESS for a customer whose ID is 6 −
UPDATE CUSTOMERS
SET ADDRESS = 'Pune'
WHERE ID = 6;客户表现在将具有以下记录：
CUSTOMERS table will now have the following records −
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 Pune 4500.00
7 Muffy 24 Indore 10000.00如果要修改 CUSTOMERS 表中的所有 ADDRESS 和 SALARY 列值，则不需要使用 WHERE 子句。UPDATE 查询如下：
If you want to modify all ADDRESS and SALARY column values in CUSTOMERS table, you do not need to use WHERE clause. UPDATE query would be as follows −
UPDATE CUSTOMERS
SET ADDRESS = 'Pune', SALARY = 1000.00;CUSTOMERS 表现在将具有以下记录。
CUSTOMERS table will now have the following records.
ID NAME AGE ADDRESS SALARY
1 Ramesh 32 Pune 1000.00
2 Khilan 25 Pune 1000.00
3 kaushik 23 Pune 1000.00
4 Chaitali 25 Pune 1000.00
5 Hardik 27 Pune 1000.00
6 Komal 22 Pune 1000.00
7 Muffy 24 Pune 1000.00