Django: Getting Started Transcripts
Chapter: Posting Data
Lecture: Adding constraints to the 'ReviewModel'
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0:00
Database constraints, on the other hand, go in a meta inter class configuration area.
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You've seen this area before to configure things like the default sort order, the name of the model in the admin, and to create database indexes.
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In this case, the constraints attribute of the meta inter class is used to add a database constraint.
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The constraints themselves are found in the models module. Here I'm using the unique constraint constraint.
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It ensures that fields in this constraint are unique when used together. In this specific case, a review must be unique to a user and a book
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Together, users won't be able to submit multiple reviews for the same book. Most constraints require a name field.
0:46
This has to do with the underlying configuration of the database. Alright, that's the model. Let me show you the corresponding admin code.