Support for WHERE NOT EXISTS

[nremond]

It would be nice to be able to do some conditional inserts.

For example, if we have the following table:

    +----------+----------+
    | user_id  | store_id |
    +----------+----------+
    |    39    |    8     |
    |    8     |    39    |
    |    5     |    11    |
    +----------+----------+

I would like to be able to run the following query:

INSERT INTO favorite_store (user_id, store_id) VALUES (39, 8)
WHERE NOT EXISTS 
    (SELECT * FROM favorite_store WHERE user_id = 39 AND store_id = 8)

[neelvk]

I would love to have this functionality. Currently, I am doing a query to figure out if I am about to insert a duplicate...

[szeiger]

#782 should take care of some of these use cases, although explicit primary keys (not defined via O.PrimaryKey) are still somewhat broken (in general, not just for insertOrUpdate) and it doesn't address the issue for non-pk columns at all.

[cvogt]

lets look into it for 2.2, but low priority

[erdebee]

+1, I'd like to see this in the DSL very much!

[nikkatalnikov]

any progress on this issue?

[hvesalai]

It's in the feature ideas box, so it is waiting for community contributions. If you would like to work on it, it is up for grabs.

[sebastianrozyczka]

@nremond Very old thread, but this is now supported by the slick API, so the issue can be closed so as not to confuse anyone :)