Re: WIP patch for LATERAL subqueries
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Amit Kapila <amit.kapila@huawei.com>, pgsql-hackers@postgresql.org
Date: 2012-08-06T15:09:09Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes: > I think you can always simulate CROSS APPLY using LATERAL. The syntax > is different but the functionality is the same. However, OUTER APPLY > allows you to do something that I don't think is possible using > LATERAL. Uh, what exactly? AFAICT from that blog entry, "x OUTER APPLY y" is exactly the same as "x LEFT JOIN LATERAL y ON true". Okay, so you saved three words, but is that a good enough reason to invent a nonstandard syntax? regards, tom lane