@smitpatel note this filter to only accept inner joins over tables (since that's what PG USING does/supports).

Little sad that only inner join is supported. I will add test which uses multiple inner joins. What do you think about cross apply?

Yeah, I agree it's sad... Good to add some more tests (multiple inner joins, left/cross...).

I'll take a look at whether USING allows cross apply (lateral join as PG calls it). My gut says no.

@smitpatel unfortunately cross apply (lateral join) doesn't work with DELETE's USING:

DELETE FROM "Order Details" AS o
USING (
    SELECT o0."OrderID", o0."CustomerID", o0."EmployeeID", o0."OrderDate"
    FROM "Orders" AS o0
    WHERE o0."OrderID" < o."OrderID"
    ORDER BY o0."OrderID" NULLS FIRST
    LIMIT 100 OFFSET 0
) AS t
WHERE o."OrderID" < 10276

This errors with:

42P01: invalid reference to FROM-clause entry for table "o"

Note that it is apparently possible to do it with UPDATE's FROM, as here:

UPDATE x
SET foo=bar
FROM a, LATERAL (...)

I tried putting LATERAL betwen the subquery and USING in the DELETE above and that didn't work either 😢

Does it work in id in subquery form?

You mean the default behavior with the PK comparison? Sure, here's your test which passes. It's just that DELETE"s USING clause is apparently only for inner joins...

@smitpatel here's the conversion to the PG-specific delete expression, as discussed in #2449 (comment). I think it does make it nicer, and query SQL generation is now trivial as it should be. Any thoughts?