regarding the key primaries composit

Hello

My parent table with composit primary key on two columns.

I need to use these two foreign key columns in the child table.

After you create the parent table, I am facing problem to create the child table, it still shows no unique primary key found

is it possible to do like this?


Kind regards
SH

While composite primary keys are legal in data modeling, a lot of people don't like them when it comes to practice. This is partly because they take more space and require more typing (additional join clauses) and partly because of a suspicion that composite keys are more likely to evolve and therefore more troubled over the lifetime of the database.

It is common to treat the composite key as if it were a key to the business: ensure uniqueness with a unique constraint, but to define a (synthetic) surrogate primary key that uses a single column for foreign keys.

Cheers, APC

Tags: Database

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