Update 语句
Update 语句用于修改表中的数据。
语法:
UPDATE table_name
SET column_name = new_value
WHERE column_name = some_value
Person:
LastName |
FirstName |
Address |
City |
Nilsen |
Fred |
Kirkegt 56 |
Stavanger |
Rasmussen |
|
Storgt 67 |
|
更新某一行中的一个列
我们为last name是"Rasmussen"的人添加first name:
UPDATE Person SET FirstName = 'Nina'
WHERE LastName = 'Rasmussen'
结果:
LastName |
FirstName |
Address |
City |
Nilsen |
Fred |
Kirkegt 56 |
Stavanger |
Rasmussen |
Nina |
Storgt 67 |
|
更新某一行中的若干列
我们会修改地址(address),并添加城市名称(name of the city):
UPDATE Person
SET Address = 'Stien 12', City = 'Stavanger'
WHERE LastName = 'Rasmussen'
结果:
LastName |
FirstName |
Address |
City |
Nilsen |
Fred |
Kirkegt 56 |
Stavanger |
Rasmussen |
Nina |
Stien 12 |
Stavanger |