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From Chris Joysn
Subject Fwd: Very slow query performance when using CTE
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Msg-id CAKRYhW1RwatKHzsYFXMjLUOcTONi1ZcLy6NAz12O6HwZQ7Rn7w@mail.gmail.com
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In response to Very slow query performance when using CTE  (Chris Joysn <joysn71@gmail.com>)
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unfortunately that increased the query execution time by a factor of 8:


On Tue, 1 Apr 2025 at 16:28, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Chris Joysn <joysn71@gmail.com> writes:
> I have an issue when using CTEs. A query, which consists of multiple CTEs,
> runs usually rather fast (~5s on my environment). But it turned out that
> using one CTE can lead to execution times of up to one minute.
> That CTE is used two times within the query.

Try labeling that CTE as NOT MATERIALIZED.

                        regards, tom lane

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