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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tatsuo Ishii <ishii@postgresql.org>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: subquery and sub-SELECT
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Comments: In-reply-to Tatsuo Ishii <ishii@postgresql.org>
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Tatsuo Ishii <ishii@postgresql.org> writes:
> In our documentations, "subquery", "sub-query", "sub-select" and
> "sub-SELECT" are used. In English, are they interchangeable?

Pretty nearly.  I think "sub-query" can include DML such as
INSERT RETURNING, whereas "sub-select" should only be a SELECT.
(I'm not claiming that we've been perfectly accurate about
that distinction.)  The dashes definitely don't matter.

			regards, tom lane