SQL Server中多對多關係的實現

標籤：

多對多的關係必須另外添加一張表來表示

--班級create table banji(banji_id int constraint PK_banji primary key,  --主鍵banji_num int not null,banji_name nvarchar(20) )--教師create table jiaoshi(jiaoshi_id int constraint PK_jaioshi primary key,  --主鍵jiaoshi_name nvarchar(20) not null)--班級和教師的關係create table banji_jiaoshi_mapping(banji_id int constraint FK_bnaji_id foreign key references banji(banji_id),    --外鍵jiaoshi_id int constraint FK_jaoshi_id foreign key references jiaoshi(jiaoshi_id),   --外鍵kecheng nvarchar(20),constraint PK_banji_id_jiaoshi_id primary key (banji_id, jiaoshi_id, kecheng)    --benji_id, jiaoshi_id, kecheng的三者組合作為主鍵)

 

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SQL Server中多對多關係的實現