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Re: Optimizing projections containing unused columns

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gj=# explain select count(*) from smartarse where v is null;
----------------------------------------------------------------
Aggregate  (cost=21.62..21.63 rows=1 width=0)
<   ->  Seq Scan on smartarse  (cost=0.00..21.60 rows=6 width=0)

Thread question and sample was about using nested queries.
Your sample does not use nested queries but it shows (width=0) that all columns are excluded.

So I do'nt understand how this applies to topic.

Andrus.

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