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From: Greg Rychlewski <[email protected]>
To: [email protected]
Subject: nested loop joins
Date: Tue, 26 Oct 2021 14:47:50 -0400
Message-ID: <CAKemG7Xi_3eS+wT97ENWbzAmpwoVHJ5=YbQQcnswo5G5qHaNMw@mail.gmail.com> (raw)

Hi,

I'm looking to understand how nested loop joins with limits work. Say I
have this query

SELECT *
FROM a  INNER JOIN b ON a.id = b.id
LIMIT 10;

Say this was done as a nested loop join where the rows of "a" are the outer
loop.

In this scenario, would all the rows of "a" be materialized or are they
lazily evaluated?

If they are lazily evaluated is it done using cursors?

Thanks

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