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atwebb on Jan 24, 2014 | parent | context | favorite | on: Use SQL subqueries to count distinct 50x faster

Am I incorrect in stating that this isn't necessarily true? Just because a statement is earlier in a script doesn't mean it will be optimized first.

joevandyk on Jan 24, 2014 [–]

In Postgres, common table expressions are planned and executed separately.

I think of it as each section builds a temp table.

This can be a good or bad thing, but it's sometimes important to know that it's happening.

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