postgresql/contrib
Michael Paquier 1d477a907e Fix row tracking in pg_stat_statements with extended query protocol
pg_stat_statements relies on EState->es_processed to count the number of
rows processed by ExecutorRun().  This proves to be a problem under the
extended query protocol when the result of a query is fetched through
more than one call of ExecutorRun(), as es_processed is reset each time
ExecutorRun() is called.  This causes pg_stat_statements to report the
number of rows calculated in the last execute fetch, rather than the
global sum of all the rows processed.

As pquery.c tells, this is a problem when a portal does not use
holdStore.  For example, DMLs with RETURNING would report a correct
tuple count as these do one execution cycle when the query is first
executed to fill in the portal's store with one ExecutorRun(), feeding
on the portal's store for each follow-up execute fetch depending on the
fetch size requested by the client.

The fix proposed for this issue is simple with the addition of an extra
counter in EState that's preserved across multiple ExecutorRun() calls,
incremented with the value calculated in es_processed.  This approach is
not back-patchable, unfortunately.

Note that libpq does not currently give any way to control the fetch
size when using the extended v3 protocol, meaning that in-core testing
is not possible yet.  This issue can be easily verified with the JDBC
driver, though, with *autocommit disabled*.  Hence, having in-core tests
requires more features, left for future discussion:
- At least two new libpq routines splitting PQsendQueryGuts(), one for
the bind/describe and a second for a series of execute fetches with a
custom fetch size, likely in a fashion similar to what JDBC does.
- A psql meta-command for the execute phase.  This part is not strictly
mandatory, still it could be handy.

Reported-by: Andrew Dunstan (original discovery by Simon Siggs)
Author: Sami Imseih
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/EBE6C507-9EB6-4142-9E4D-38B1673363A7@amazon.com
Discussion: https://postgr.es/m/c90890e7-9c89-c34f-d3c5-d5c763a34bd8@dunslane.net
2023-04-06 09:29:03 +09:00
..
adminpack Use "data directory" not "current directory" in error messages. 2023-03-16 12:04:08 -04:00
amcheck Pass down table relation into more index relation functions 2023-04-01 20:18:29 -07:00
auth_delay Fix copy-pasto in contrib/auth_delay/meson.build variable name. 2023-04-02 09:31:10 -07:00
auto_explain Make auto_explain print the query identifier in verbose mode 2023-01-26 12:23:16 +09:00
basebackup_to_shell Common function for percent placeholder replacement 2023-01-11 10:42:35 +01:00
basic_archive Redesign archive modules 2023-02-17 14:26:42 +09:00
bloom Update types in smgr API 2023-02-27 07:47:46 +01:00
bool_plperl Update copyright for 2023 2023-01-02 15:00:37 -05:00
btree_gin Update copyright for 2023 2023-01-02 15:00:37 -05:00
btree_gist Remove useless casts to (void *) in arguments of some system functions 2023-02-07 06:57:59 +01:00
citext Use ICU by default at initdb time. 2023-03-09 10:52:41 -08:00
cube Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
dblink dblink: Fix variable confusion introduced in e4602483e9 2023-01-31 17:47:53 -08:00
dict_int Update copyright for 2023 2023-01-02 15:00:37 -05:00
dict_xsyn Update copyright for 2023 2023-01-02 15:00:37 -05:00
earthdistance Doc: improve commentary about providing our own definitions of M_PI. 2023-01-08 16:25:33 -05:00
file_fdw Improve several permission-related error messages. 2023-03-17 10:33:09 +01:00
fuzzystrmatch New header varatt.h split off from postgres.h 2023-01-10 05:54:36 +01:00
hstore Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
hstore_plperl Update copyright for 2023 2023-01-02 15:00:37 -05:00
hstore_plpython Update copyright for 2023 2023-01-02 15:00:37 -05:00
intagg Update copyright for 2023 2023-01-02 15:00:37 -05:00
intarray Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
isn Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
jsonb_plperl Update copyright for 2023 2023-01-02 15:00:37 -05:00
jsonb_plpython Update copyright for 2023 2023-01-02 15:00:37 -05:00
lo Update copyright for 2023 2023-01-02 15:00:37 -05:00
ltree Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
ltree_plpython Update copyright for 2023 2023-01-02 15:00:37 -05:00
oid2name Mark options as deprecated in usage output 2023-03-02 14:36:37 +01:00
old_snapshot Update copyright for 2023 2023-01-02 15:00:37 -05:00
pageinspect pageinspect: Fix crash with gist_page_items() 2023-03-02 14:03:02 +09:00
passwordcheck Update copyright for 2023 2023-01-02 15:00:37 -05:00
pg_buffercache Update copyright for 2023 2023-01-02 15:00:37 -05:00
pg_freespacemap Update copyright for 2023 2023-01-02 15:00:37 -05:00
pg_prewarm Update copyright for 2023 2023-01-02 15:00:37 -05:00
pg_stat_statements Fix row tracking in pg_stat_statements with extended query protocol 2023-04-06 09:29:03 +09:00
pg_surgery Remove useless casts to (void *) in arguments of some system functions 2023-02-07 06:57:59 +01:00
pg_trgm Fix misbehavior in contrib/pg_trgm with an unsatisfiable regex. 2023-03-11 12:15:41 -05:00
pg_visibility Update copyright for 2023 2023-01-02 15:00:37 -05:00
pg_walinspect Add show_data option to pg_get_wal_block_info. 2023-03-31 14:02:52 -07:00
pgcrypto New header varatt.h split off from postgres.h 2023-01-10 05:54:36 +01:00
pgrowlocks Update copyright for 2023 2023-01-02 15:00:37 -05:00
pgstattuple Update copyright for 2023 2023-01-02 15:00:37 -05:00
postgres_fdw Fix function reference in comment 2023-04-05 09:06:32 +02:00
seg Rework pg_input_error_message(), now renamed pg_input_error_info() 2023-02-28 08:04:13 +09:00
sepgsql Remove bms_first_member(). 2023-03-02 11:34:29 -05:00
spi Update copyright for 2023 2023-01-02 15:00:37 -05:00
sslinfo Update copyright for 2023 2023-01-02 15:00:37 -05:00
start-scripts Remove gratuitous references to postmaster program 2023-01-26 10:48:32 +01:00
tablefunc Update copyright for 2023 2023-01-02 15:00:37 -05:00
tcn Update copyright for 2023 2023-01-02 15:00:37 -05:00
test_decoding Improve several permission-related error messages. 2023-03-17 10:33:09 +01:00
tsm_system_rows Update copyright for 2023 2023-01-02 15:00:37 -05:00
tsm_system_time Update copyright for 2023 2023-01-02 15:00:37 -05:00
unaccent Fix t_isspace(), etc., when datlocprovider=i and datctype=C. 2023-03-17 12:08:46 -07:00
uuid-ossp New header varatt.h split off from postgres.h 2023-01-10 05:54:36 +01:00
vacuumlo Update copyright for 2023 2023-01-02 15:00:37 -05:00
xml2 Update copyright for 2023 2023-01-02 15:00:37 -05:00
contrib-global.mk Respect TEMP_CONFIG when pg_regress_check and friends are called 2016-02-27 12:28:21 -05:00
Makefile Revert "Rename contrib module basic_archive to basic_wal_module" 2023-01-26 09:13:39 +09:00
meson.build Revert "Rename contrib module basic_archive to basic_wal_module" 2023-01-26 09:13:39 +09:00
README Rename 'gmake' to 'make' in docs and recommended commands 2014-02-12 17:29:19 -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
because they address a limited audience or are too experimental to be
part of the main source tree.  This does not preclude their
usefulness.

User documentation for each module appears in the main SGML
documentation.

When building from the source distribution, these modules are not
built automatically, unless you build the "world" target.  You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.

Some directories supply new user-defined functions, operators, or
types.  To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command.  In a fresh database,
you can simply do

    CREATE EXTENSION module_name;

See the PostgreSQL documentation for more information about this
procedure.