SQL Server 新闻门户网站数据库设计与实现

SQL Server 新闻门户网站数据库设计与实现

create database sc; use sc; create table Admin( adminId int identity(201301,1)primary key, adminName varchar(255) unique not null, pswd varchar(255) not null ); CREATE TABLE Category ( categoryId int identity(1,1) primary key, categoryName varchar(255) unique NOT NULL, counter int DEFAULT 0 ); create table Article( articleId int identity(1,1) primary key, title varchar(255) not null, content ntext , time date not null, categoryId int not null, foreign key (categoryId) references Category(categoryId) on delete no action on update cascade ); /*触发器 添加一条新闻，对应新闻项总数加一*/ create trigger articleInsert on Article for Insert as declare @categoryId int Begin select @categoryId = categoryId from inserted update Category set counter = counter + 1 where categoryId = @categoryId End /*触发器 删除一条新闻，对应新闻项总数减一*/ create trigger articleDelete on Article for delete as declare @categoryId int Begin select @categoryId = categoryId from deleted update Category set counter = counter - 1 where categoryId = @categoryId End

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