Re: Why NESTED LOOP Not Allowed for FULL and RIGHT Join.

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Rushabh Lathia" <rushabh(dot)lathia(at)gmail(dot)com>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Why NESTED LOOP Not Allowed for FULL and RIGHT Join.
Date: 2007-08-20 14:09:38
Message-ID: 29438.1187618978@sss.pgh.pa.us
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"Rushabh Lathia" <rushabh(dot)lathia(at)gmail(dot)com> writes:
> can anyone let me know that why Nested Loop path is not allowed if jointype
> are JOIN_RIGHT or JOIN_FULL?

How are you going to track which of the inner-relation rows never find a
join partner and hence need to be emitted on their own?

regards, tom lane

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