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aa86129e19
Hash joins can support semijoin with the LHS input on the right, using the existing logic for inner join, combined with the assurance that only the first match for each inner tuple is considered, which can be achieved by leveraging the HEAP_TUPLE_HAS_MATCH flag. This can be very useful in some cases since we may now have the option to hash the smaller table instead of the larger. Merge join could likely support "Right Semi Join" too. However, the benefit of swapping inputs tends to be small here, so we do not address that in this patch. Note that this patch also modifies a test query in join.sql to ensure it continues testing as intended. With this patch the original query would result in a right-semi-join rather than semi-join, compromising its original purpose of testing the fix for neqjoinsel's behavior for semi-joins. Author: Richard Guo Reviewed-by: wenhui qiu, Alena Rybakina, Japin Li Discussion: https://postgr.es/m/CAMbWs4_X1mN=ic+SxcyymUqFx9bB8pqSLTGJ-F=MHy4PW3eRXw@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_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.