postgresql/src/test/regress/sql/sysviews.sql
Michael Paquier 1e68e43d3f Add system view pg_wait_events
This new view, wrapped around a SRF, shows some information known about
wait events, as of:
- Name.
- Type (Activity, I/O, Extension, etc.).
- Description.

All the information retrieved comes from wait_event_names.txt, and the
description is the same as the documentation with filters applied to
remove any XML markups.  This view is useful when joined with
pg_stat_activity to get the description of a wait event reported.

Custom wait events for extensions are included in the view.

Original idea by Yves Colin.

Author: Bertrand Drouvot
Reviewed-by: Kyotaro Horiguchi, Masahiro Ikeda, Tom Lane, Michael
Paquier
Discussion: https://postgr.es/m/0e2ae164-dc89-03c3-cf7f-de86378053ac@gmail.com
2023-08-20 15:35:02 +09:00

74 lines
3.1 KiB
SQL

--
-- Test assorted system views
--
-- This test is mainly meant to provide some code coverage for the
-- set-returning functions that underlie certain system views.
-- The output of most of these functions is very environment-dependent,
-- so our ability to test with fixed expected output is pretty limited;
-- but even a trivial check of count(*) will exercise the normal code path
-- through the SRF.
select count(*) >= 0 as ok from pg_available_extension_versions;
select count(*) >= 0 as ok from pg_available_extensions;
-- The entire output of pg_backend_memory_contexts is not stable,
-- we test only the existence and basic condition of TopMemoryContext.
select name, ident, parent, level, total_bytes >= free_bytes
from pg_backend_memory_contexts where level = 0;
-- At introduction, pg_config had 23 entries; it may grow
select count(*) > 20 as ok from pg_config;
-- We expect no cursors in this test; see also portals.sql
select count(*) = 0 as ok from pg_cursors;
select count(*) >= 0 as ok from pg_file_settings;
-- There will surely be at least one rule, with no errors.
select count(*) > 0 as ok, count(*) FILTER (WHERE error IS NOT NULL) = 0 AS no_err
from pg_hba_file_rules;
-- There may be no rules, and there should be no errors.
select count(*) >= 0 as ok, count(*) FILTER (WHERE error IS NOT NULL) = 0 AS no_err
from pg_ident_file_mappings;
-- There will surely be at least one active lock
select count(*) > 0 as ok from pg_locks;
-- We expect no prepared statements in this test; see also prepare.sql
select count(*) = 0 as ok from pg_prepared_statements;
-- See also prepared_xacts.sql
select count(*) >= 0 as ok from pg_prepared_xacts;
-- There will surely be at least one SLRU cache
select count(*) > 0 as ok from pg_stat_slru;
-- There must be only one record
select count(*) = 1 as ok from pg_stat_wal;
-- We expect no walreceiver running in this test
select count(*) = 0 as ok from pg_stat_wal_receiver;
-- This is to record the prevailing planner enable_foo settings during
-- a regression test run.
select name, setting from pg_settings where name like 'enable%';
-- There are always wait event descriptions for various types.
select type, count(*) > 0 as ok FROM pg_wait_events
group by type order by type COLLATE "C";
-- Test that the pg_timezone_names and pg_timezone_abbrevs views are
-- more-or-less working. We can't test their contents in any great detail
-- without the outputs changing anytime IANA updates the underlying data,
-- but it seems reasonable to expect at least one entry per major meridian.
-- (At the time of writing, the actual counts are around 38 because of
-- zones using fractional GMT offsets, so this is a pretty loose test.)
select count(distinct utc_offset) >= 24 as ok from pg_timezone_names;
select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
-- Let's check the non-default timezone abbreviation sets, too
set timezone_abbreviations = 'Australia';
select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
set timezone_abbreviations = 'India';
select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;