mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-08-13 14:53:24 +02:00
VACUUM thought that reltuples represents the total number of tuples in the relation, while ANALYZE counted only live tuples. This can cause "flapping" in the value when background vacuums and analyzes happen separately. The planner's use of reltuples essentially assumes that it's the count of live (visible) tuples, so let's standardize on having it mean live tuples. Another issue is that the definition of "live tuple" isn't totally clear; what should be done with INSERT_IN_PROGRESS or DELETE_IN_PROGRESS tuples? ANALYZE's choices in this regard are made on the assumption that if the originating transaction commits at all, it will happen after ANALYZE finishes, so we should ignore the effects of the in-progress transaction --- unless it is our own transaction, and then we should count it. Let's propagate this definition into VACUUM, too. Likewise propagate this definition into CREATE INDEX, and into contrib/pgstattuple's pgstattuple_approx() function. Tomas Vondra, reviewed by Haribabu Kommi, some corrections by me Discussion: https://postgr.es/m/16db4468-edfa-830a-f921-39a50498e77e@2ndquadrant.com |
||
---|---|---|
.. | ||
adminpack | ||
amcheck | ||
auth_delay | ||
auto_explain | ||
bloom | ||
btree_gin | ||
btree_gist | ||
citext | ||
cube | ||
dblink | ||
dict_int | ||
dict_xsyn | ||
earthdistance | ||
file_fdw | ||
fuzzystrmatch | ||
hstore | ||
hstore_plperl | ||
hstore_plpython | ||
intagg | ||
intarray | ||
isn | ||
lo | ||
ltree | ||
ltree_plpython | ||
oid2name | ||
pageinspect | ||
passwordcheck | ||
pg_buffercache | ||
pg_freespacemap | ||
pg_prewarm | ||
pg_standby | ||
pg_stat_statements | ||
pg_trgm | ||
pg_visibility | ||
pgcrypto | ||
pgrowlocks | ||
pgstattuple | ||
postgres_fdw | ||
seg | ||
sepgsql | ||
spi | ||
sslinfo | ||
start-scripts | ||
tablefunc | ||
tcn | ||
test_decoding | ||
tsm_system_rows | ||
tsm_system_time | ||
unaccent | ||
uuid-ossp | ||
vacuumlo | ||
xml2 | ||
contrib-global.mk | ||
Makefile | ||
README |
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.