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A comment on Modern Data Practice and the SQL Tradition. Parent comment

Re:Modern Data Practice and the SQL Tradition by gigatexal on Friday November 08, 2019 @10:39AM (#21483165)
Be wary of WITH statements as they are optimization barriers as some engines can't optimize them -- that's changing but just FYI. I believe the latest Postgres release is handling them properly now -- I could be wrong.
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Re:Modern Data Practice and the SQL Tradition by alexhutcheson on Friday November 08, 2019 @10:43AM (#21483222)
Good note. Subqueries are sometimes optimization barriers as well - it depends on query engine. If you care about performance you need to look at the query plan.
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Re:Modern Data Practice and the SQL Tradition by gigatexal on Friday November 08, 2019 @11:03AM (#21483483)
"If you care about performance you need to look at the query plan." Always I would say, once your data gets above toy size.
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