Fujii Masao 4a539a25eb Expose BufferUsageAccumDiff().
Previously pg_stat_statements calculated the difference of buffer counters
by its own code even while BufferUsageAccumDiff() had the same code.
This commit expose BufferUsageAccumDiff() and makes pg_stat_statements
use it for the calculation, in order to simply the code.

This change also would be useful for the upcoming patch for the planning
counters in pg_stat_statements because the patch will add one more code
for the calculation of difference of buffer counters and that can easily be
done by using BufferUsageAccumDiff().

Author: Julien Rouhaud
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/bdfee4e0-a304-2498-8da5-3cb52c0a193e@oss.nttdata.com
2020-03-30 12:15:26 +09:00
..
2020-01-01 12:21:45 -05:00
2020-01-01 12:21:45 -05:00
2020-02-24 18:43:40 -05:00
2020-03-09 09:34:55 +01:00
2020-01-01 12:21:45 -05:00
2020-02-24 18:43:40 -05:00

The PostgreSQL contrib tree
---------------------------

This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
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User documentation for each module appears in the main SGML
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When building from the source distribution, these modules are not
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See the PostgreSQL documentation for more information about this
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