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0 pointsmalisper9y ago0 comments

This is roughly EAV. EAV is where you have a with a schema:

    entity_id | attribute_id | value

EAV is typically considered to be an anti-pattern for several reasons: it becomes very expensive to rematerialize a entity with all of its attributes/values, it becomes difficult to have any kind of constraints on the values (this is also a problem with jsonb), and it's hard for the database to maintain good statistics on the values of different attributes as most databases don't keep multi-column statistics. Don't worry, I've had similar ideas before.

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strommen9y ago

EAV is an anti-pattern?

If you don't have JSONB, EAV is the only remotely-reasonable way to implement user-defined fields (e.g. product-specific attributes in e-commerce).

malisperOP9y ago

If you want to allow user-defined fields in a relational database, your realistic are either EAV or stuff json into a text column. EAV, if done extremely carefully, can be a good solution, but 99% of the time, it's going to be a huge pain.

approachingtraj9y ago

> stuff json into a text column

You did see the article was about JSONB, which is significantly more sophisticated than "json in a text column", yes?

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