Re: Generating "Subplan Removed" in EXPLAIN

On Tue, Jan 31, 2023 at 08:59:57PM -0500, Bruce Momjian wrote:
> Our document states that EXPLAIN can generate "Subplan Removed":
>
> https://www.postgresql.org/docs/current/ddl-partitioning.html#DDL-PARTITION-PRUNING
>
> It is possible to determine the number of partitions which were removed
> during this phase by observing the “Subplans Removed” property in the
> EXPLAIN output.

Sorry, here is the full paragraph:

During initialization of the query plan. Partition pruning can
be performed here for parameter values which are known during
the initialization phase of execution. Partitions which are
pruned during this stage will not show up in the query's EXPLAIN
or EXPLAIN ANALYZE. It is possible to determine the number of
partitions which were removed during this phase by observing the
“Subplans Removed” property in the EXPLAIN output.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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