Show names of DEALLOCATE as constants in pg_stat_statements
This commit switches query jumbling so as prepared statement names are
treated as constants in DeallocateStmt. A boolean field is added to
DeallocateStmt to make a distinction between ALL and named prepared
statements, as "name" was used to make this difference before, NULL
meaning DEALLOCATE ALL.
Prior to this commit, DEALLOCATE was not tracked in pg_stat_statements,
for the reason that it was not possible to treat its name parameter as a
constant. Now that query jumbling applies to all the utility nodes,
this reason does not apply anymore.
Like 638d42a3c520, this can be a huge advantage for monitoring where
prepared statement names are randomly generated, preventing bloat in
pg_stat_statements. A couple of tests are added to track the new
behavior.
Author: Dagfinn Ilmari Mannsåker, Michael Paquier
Reviewed-by: Julien Rouhaud
Discussion: https://postgr.es/m/ZMhT9kNtJJsHw6jK@paquier.xyz
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/bb45156f342c2cdb88cdd7f9efdc4541e910ec86
Modified Files
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contrib/pg_stat_statements/expected/utility.out | 41 +++++++++++++++++++++++++
contrib/pg_stat_statements/pg_stat_statements.c | 8 ++---
contrib/pg_stat_statements/sql/utility.sql | 13 ++++++++
src/backend/parser/gram.y | 8 +++++
src/include/nodes/parsenodes.h | 8 +++--
5 files changed, 70 insertions(+), 8 deletions(-)