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Date: Tue, 18 Jan 2022 19:09:55 -0500
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Subject: Re: Large number of partitions of a table
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From: Mladen Gogala <gogala.mladen@gmail.com>
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On 1/18/22 09:47, Ron wrote:
> EXPLAIN plans are going to be hilariously gigantic, which means that 
> query planning would take a loooong time,  And the query planner (in 
> v12, at least) can generate some pretty bad plans in partitioned 
> tables; I bet there are edge cases in the QP code that don't work well 
> with 10000 partitions and 50000 indices.

These things sometimes happen. On the oracle-l, there is a thread in 
progress about a generated SQL with 130,000 lines which fails parsing 
because parsing exhausts the available memory. In such cases, I am less 
inclined to look for a fault with the database software and more 
inclined to inflict an unusual and cruel punishment on whoever has 
designed the data model.

-- 
Mladen Gogala
Database Consultant
Tel: (347) 321-1217
https://dbwhisperer.wordpress.com

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    <div class="moz-cite-prefix">On 1/18/22 09:47, Ron wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:d45899c8-187d-4a1d-563b-f5842243e770@gmail.com">EXPLAIN
      plans are going to be hilariously gigantic, which means that query
      planning would take a loooong time,  And the query planner (in
      v12, at least) can generate some pretty bad plans in partitioned
      tables; I bet there are edge cases in the QP code that don't work
      well with 10000 partitions and 50000 indices.</blockquote>
    <p>These things sometimes happen. On the oracle-l, there is a thread
      in progress about a generated SQL with 130,000 lines which fails
      parsing because parsing exhausts the available memory. In such
      cases, I am less inclined to look for a fault with the database
      software and more inclined to inflict an unusual and cruel
      punishment on whoever has designed the data model.<br>
    </p>
    <pre class="moz-signature" cols="72">-- 
Mladen Gogala
Database Consultant
Tel: (347) 321-1217
<a class="moz-txt-link-freetext" href="https://dbwhisperer.wordpress.com">https://dbwhisperer.wordpress.com</a>
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