Re: What does "merge-joinable join conditions" mean ????

"Dean Gibson (DB Administrator)" <postgresql4(at)ultimeth(dot)com> writes:
> SELECT count(*) FROM "GenAppExtra" FULL JOIN "GeoRestrict" ON callsign
> ~ pattern WHERE region_id = 4 OR geo_region = 4;

> If either of the "region_id = 4" (a field in the right-hand table) or
> "geo_region = 4" (a field in the left-hand table) are removed, the
> SELECT functions (does not give an error message),

Really? The FULL JOIN condition using ~ is the source of the failure,
and I'd be quite surprised if changing WHERE makes it work.

regards, tom lane