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ce8d5fe0e2
Previously, we always fed SELECT ... INTO to the SPI machinery. While that works for all cases, it's a great deal slower than the otherwise-equivalent "var := expression" if the expression is "simple" and the INTO target is a single variable. Users coming from MSSQL or T_SQL are likely to be surprised by this; they are used to writing SELECT ... INTO since there is no "var := expression" syntax in those dialects. Hence, check for a simple expression and use the faster code path if possible. (Here, "simple" means whatever exec_is_simple_query accepts, which basically means "SELECT scalar-expression" without any input tables, aggregates, qual clauses, etc.) This optimization is not entirely transparent. Notably, one of the reasons it's faster is that the hooks that pg_stat_statements uses aren't called in this path, so that the evaluated expression no longer appears in pg_stat_statements output as it did before. There may be some other minor behavioral changes too, although I tried hard to make error reporting look the same. Hopefully, none of them are significant enough to not be acceptable as routine changes in a PG major version. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com> Discussion: https://postgr.es/m/CAFj8pRDieSQOPDHD_svvR75875uRejS9cN87FoAC3iXMXS1saQ@mail.gmail.com |
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| .. | ||
| amcheck | ||
| auth_delay | ||
| auto_explain | ||
| basebackup_to_shell | ||
| basic_archive | ||
| bloom | ||
| bool_plperl | ||
| btree_gin | ||
| btree_gist | ||
| citext | ||
| cube | ||
| dblink | ||
| dict_int | ||
| dict_xsyn | ||
| earthdistance | ||
| file_fdw | ||
| fuzzystrmatch | ||
| hstore | ||
| hstore_plperl | ||
| hstore_plpython | ||
| intagg | ||
| intarray | ||
| isn | ||
| jsonb_plperl | ||
| jsonb_plpython | ||
| lo | ||
| ltree | ||
| ltree_plpython | ||
| oid2name | ||
| pageinspect | ||
| passwordcheck | ||
| pg_buffercache | ||
| pg_freespacemap | ||
| pg_logicalinspect | ||
| pg_overexplain | ||
| pg_plan_advice | ||
| pg_prewarm | ||
| pg_stat_statements | ||
| pg_surgery | ||
| pg_trgm | ||
| pg_visibility | ||
| pg_walinspect | ||
| 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 | ||
| meson.build | ||
| 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.