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I'm using Microsoft SQL Server 2008 Management Studio to create a relational schema by following an Entity-Relationship diagram. (included below; unrelated details removed)

entity-relationship diagram with weak entity set

Until now, primary and foreign keys have been working as expected. But when I try to create a foreign key from the entity relationship takes onto the weak entity set section, I get an error. Section is identified by a composite primary key in the context of course, which has course_id as a primary key. Therefore, the primary key of section is a 4-way composite key.

The entity relationship takes needs to refer to section, so it includes all 4 primary attributes from section in it's own primary key. When trying to establish a foreign key relationship from takes to section, Studio gives the following error:

The columns in table 'section' do not match an existing primary key or UNIQUE constraint.

Am I doing something wrong, or is this an unsupported configuration? I can provide more details or the SQL schema if necessary.

A: 

The ordering of attributes in the primary and foreign key must be maintained.

(I was getting an error because the attributes of the foreign key were being specified in a different order than they occurred in the primary key.)

Nic

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