database design - Will junction table contain the foreign keys or the primary keys of the individual tables -

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in link here

they explain how use junction tables around many-many relationship problem in relational database design.

this line

if there no association class, junction table (sometimes called join table or linking table) contain fk attributes each side of association.

from example seems junction table containing not fk primary keys of individual tables. cust id, order date form composite primary key of orders , upc primary key of products.

correct. 'junction' table or 'association' table contain pk values of tables on either end of m2m relationship. times these 2 columns in association/junction table , can/usually form pk of association/junction table.


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