sql server - relationship many to many -

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i want create database relationship many many. have error

sql71516 :: referenced table '[dbo].[bookauthors]' contains no primary or candidate keys match referencing column list in foreign key. if referenced column computed column, should persisted. sql71516 :: referenced table '[dbo].[bookauthors]' contains no primary or candidate keys match referencing column list in foreign key. if referenced column computed column, should persisted.

how fix this?

create table [dbo].[bookauthors] (     [book]   int not null,     [author] int not null,     primary key clustered ([book] asc,[author] asc) );  create table [dbo].[books] (     [id]       int            not null,     [title]    nvarchar (max) null,     [price]    money          null,     [category] int            null,     primary key clustered ([id] asc),     foreign key ([id]) references [dbo].[bookauthors] ([book]) );  create table [dbo].[authors] (     [id]   int        not null,     [name] nchar (10) not null,     primary key clustered ([id]),      foreign key ([id]) references [dbo].[bookauthors] ([author]) );

you crated in bookauthors composite primary key consists of 2 columns: book , author. when referencing it, need reference both columns. other solution make in bookauthors third column (identity maybe) primary key , reference one.


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