如何使用检查约束更改 table - SQL 服务器
How to do alter table using Check Constraint - SQL Server
CREATE TABLE publishers
(
PublisherName varchar(75),
City varchar(35),
PublisherState char(2),
Country varchar(4)
)
GO
-- 修改publishers,使state必须是两个字母
ALTER TABLE publishers
ALTER COLUMN publisherstate char(2) CHECK (publisherstate LIKE '[A-Za-z][A-Za-z]')
你不得不提到 Constraint Name
和 Check
。
试试这个:
alter table publishers
add constraint codeCheck check (PublisherState like '[A-Za-z][A-Za-z]');
CREATE TABLE publishers
(
PublisherName varchar(75),
City varchar(35),
PublisherState char(2),
Country varchar(4)
)
GO
-- 修改publishers,使state必须是两个字母
ALTER TABLE publishers
ALTER COLUMN publisherstate char(2) CHECK (publisherstate LIKE '[A-Za-z][A-Za-z]')
你不得不提到 Constraint Name
和 Check
。
试试这个:
alter table publishers
add constraint codeCheck check (PublisherState like '[A-Za-z][A-Za-z]');