This section contains information regarding the standard modules which can be found in the contrib directory of the PostgreSQL distribution. These are 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. Some modules supply new user-defined functions, operators, or types. In these cases, you will need to run make and make install in contrib/module. After you have installed the files you need to register the new entities in the database system by running the commands in the supplied .sql file. For example, $ psql -d dbname -f module.sql You can modify the first command in the .sql file to control the schema where the module is created. During major upgrades, even though the restored database might already have the desired module functions, run the installation script again to add any new functions. &adminpack; &btree-gist; &chkpass; &cube; &dblink; &earthdistance; &fuzzystrmatch; &hstore; &intagg; &intarray; &isn; &lo; <ree; &oid2name; &pageinspect; &pgbench; &buffercache; &pgcrypto; &freespacemap; &pgrowlocks; &standby; &pgstattuple; &trgm; &seg; &sslinfo; &tablefunc; &uuid-ossp; &vacuumlo; &xml2;