referential-integrity

What’s wrong with foreign keys?

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I remember hearing Joel Spolsky mention in podcast 014 that he’d barely ever used a foreign key (if I remember correctly). However, to me they seem pretty vital to avoid duplication and subsequent data integrity problems throughout your database. Do people have some solid reasons as to why (to avoid a discussion in lines with … Read more

Create unique constraint with null columns

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I have a table with this layout: CREATE TABLE Favorites ( FavoriteId uuid NOT NULL PRIMARY KEY, UserId uuid NOT NULL, RecipeId uuid NOT NULL, MenuId uuid ) I want to create a unique constraint similar to this: ALTER TABLE Favorites ADD CONSTRAINT Favorites_UniqueFavorite UNIQUE(UserId, MenuId, RecipeId); However, this will allow multiple rows with the … Read more