How do I construct an `update ... from`?

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Bare bones, type-safe EDSL for SQL queries on persistent backends.

http://hackage.haskell.org/package/esqueleto

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How do I construct an `update ... from`? #116

Closed jhickner closed 8 years ago

jhickner commented 8 years ago

How would I construct an update that includes a join? In SQL it looks like this: update users u set flag = false from roles r where r.user_id = u.id

This actually compiles but results in a sql error:

update $ \u -> do
    set u [UserFlag =. False]
    from $ \r -> where_ (r ^. RoleUserId ==. u ^. UserId)

meteficha commented 8 years ago

I don't think you can do that today. You may want to try the equivalent of:

UPDATE users u 
SET flag = false
WHERE u.id IN (SELECT user_id FROM roles)