Re: LATERAL, UNNEST and spec compliance - Mailing list pgsql-hackers

Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> SELECT ... FROM a WHERE a.x IN (SELECT ... FROM b, srf(y) WHERE ...)

> Actually, this appears to fail already, at least in 9.2.2:

> => select * from (values (1)) v(a) where v.a in (select x from (values (2)) v2(a), 
> ->                     generate_series(1,a) x);
> ERROR:  function expression in FROM cannot refer to other relations of same query level
> LINE 2:                     generate_series(1,a) x);
>                                               ^

Huh ... you're right, I'd forgotten about that.  That's an ancient bug
that got fixed in passing in the LATERAL work.  So, as long as we're not
going to fix that bug in the back branches (which would be difficult
anyway IIRC), we don't have a compatibility problem ...
        regards, tom lane