subselect

From: Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
To: hackers(at)postgreSQL(dot)org (PostgreSQL-development)
Cc: vadim(at)sable(dot)krasnoyarsk(dot)su (Vadim B(dot) Mikheev)
Subject: subselect
Date: 1998-01-05 05:16:49
Message-ID: 199801050516.AAA28005@candle.pha.pa.us
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I was thinking about subselects, and how to attach the two queries.

What if the subquery makes a range table entry in the outer query, and
the query is set up like the UNION queries where we put the scans in a
row, but in the case we put them over/under each other.

And we push a temp table into the catalog cache that represents the
result of the subquery, then we could join to it in the outer query as
though it was a real table.

Also, can't we do the correlated subqueries by adding the proper
target/output columns to the subquery, and have the outer query
reference those columns in the subquery range table entry.

Maybe I can write up a sample of this? Vadim, would this help? Is this
the point we are stuck at?

--
Bruce Momjian
maillist(at)candle(dot)pha(dot)pa(dot)us

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