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Global Data in PL/TclManual ChaptersPG1842.4. Global Data in PL/Tcl Sometimes it is useful to have some global data that is held between two calls to a function or is shared between different functions. This is easily done in PL/T…Global Data in PL/Tcl Global Values in PL/PerlManual ChaptersPG1843.4. Global Values in PL/Perl You can use the global hash %_SHARED to store data, including code references, between function calls for the lifetime of the current session. Here is a simple…Global Values in PL/Perl GlossaryManual ChaptersPG18Appendix M. Glossary This is a list of terms and their meaning in the context of PostgreSQL and relational database systems in general. ACID Atomicity, Consistency, Isolation, and Durability…Glossary gms_rawExtensionsExtensionsprocess raw type data for PL/SQL applications gms_raw CompatibilityCompatibility · Extensions gms_tcpExtensionsExtensionsprovides TCP/IP client=side access functionality in PL/SQL gms_tcp CompatibilityCompatibility · Extensions go_fdwExtensionsExtensionsExperimental Go/cgo project template for building PostgreSQL foreign data wrappers. cgo fdw go template go_fdw Foreign data wrappersForeign data wrappers · Extensions godel_logicExtensionsExtensionsProvides operators to evaluate fuzzy logic expressions according to Gödel logic. fuzzy gödel logic operators product łukasiewicz fuzzy_logic Functions and aggregatesFunctions and aggregates · Extensions gofdwExtensionsExtensionsPostgres FDW in go experiments gofdw Foreign data wrappersForeign data wrappers · Extensions gogudbExtensionsExtensionsPostgreSQL extension for distributed hash and range partitioning across foreign servers. distributed-database fdw partitioning sharding gogudb AnalyticsAnalytics · Extensions goldenmatch_pgExtensionsExtensionsGoldenMatch entity-resolution functions for deduplication, matching, scoring, and golden-record workflows. deduplication entity-resolution matching pgrx goldenmatch_pg AI and vectorsAI and vectors · Extensions Good PracticesManual ChaptersPG18Good Practices It is very easy to use pgbench to produce completely meaningless numbers. Here are some guidelines to help you get useful results. In the first place, never believe any test t…Good Practices google_columnar_engineExtensionsExtensionsAlloyDB column store, planner, and execution engine for accelerating HTAP and OLAP scans, joins, and aggregates. alloydb columnar htap olap query-acceleration google_columnar_engine Analytic…Analytics · Extensions google_db_advisorExtensionsExtensionsAlloyDB index advisor extension for workload analysis and index recommendations. alloydb index-advisor performance google_db_advisor FeaturesFeatures · Extensions google_ml_integrationExtensionsExtensionsGoogle Cloud machine learning integration extension for registering model endpoints, generating embeddings, and invoking predictions from SQL. ai embeddings machine-learning model-endpoint r…AI and vectors · Extensions google_plan_managementExtensionsExtensionsPreview AlloyDB extension for tracking, approving, denying, and consistently selecting query plans. alloydb plan-stability preview query-optimizer query-plans google_plan_management Administ…Administration · Extensions gp_debug_numsegmentsExtensionsExtensionsGet or set the default number of segments used when creating tables. big-data data-analysis data-warehouse database distributed-database greenplum mpp olap open-source postgresql gp_debug_nu…Administration · Extensions gp_distribution_policyExtensionsExtensionsCheck table distribution policy in a Greenplum-family cluster. gp_distribution_policy AdministrationAdministration · Extensions gp_exttable_fdwExtensionsExtensionsExternal Table Foreign Data Wrapper for Greenplum-family databases. ai big-data c cloudberry data-analysis data-warehouse database distributed-database greenplum mpp olap postgres postgresql…Foreign data wrappers · Extensions gp_inject_faultExtensionsExtensionsSimulate faults in Greenplum-family databases for testing. gp_inject_fault FeaturesFeatures · Extensions gp_internal_toolsExtensionsExtensionsDifferent internal tools for Greenplum gp_internal_tools AdministrationAdministration · Extensions gp_sparse_vectorExtensionsExtensionsSparse vector implementation for Greenplum-family databases. ai big-data c cloudberry data-analysis data-warehouse database distributed-database greenplum mpp olap postgres postgresql sql gp…AI and vectors · Extensions gp_toolkitExtensionsExtensionsAdministrative views and functions for Greenplum-family databases. gp_toolkit AdministrationAdministration · Extensions GRANTManual ChaptersPG18GRANT GRANT — define access privileges Synopsis GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER | MAINTAIN } [, ...] | ALL [ PRIVILEGES ] } ON { [ TABLE ] table…GRANT GRANTSQL CommandsReferenceGRANT Roles & Privileges 10 define access privileges GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER } [, ...] | ALL [ PRIVILEGES ] } ON { [ TABLE ] table_name …SQL Commands · Roles & Privileges GRANT on Database ObjectsManual ChaptersPG18GRANT on Database Objects This variant of the GRANT command gives specific privileges on a database object to one or more roles. These privileges are added to those already granted, if any. …GRANT on Database Objects GRANT on RolesManual ChaptersPG18GRANT on Roles This variant of the GRANT command grants membership in a role to one or more other roles, and the modification of membership options SET, INHERIT, and ADMIN; see Section 21.3 …GRANT on Roles grants_managerExtensionsExtensionsDeclarative PL/pgSQL toolkit for snapshotting, reporting, and aligning database object grants. access-control grants permissions roles pg_grants_manager SecuritySecurity · Extensions graphExtensionsExtensionsGraph database capabilities for PostgreSQL pgrx pggraph FeaturesFeatures · Extensions graph_accelExtensionsExtensionsIn-memory graph traversal acceleration extension for Apache AGE. apache-age graph pgrx traversal graph_accel FeaturesFeatures · Extensions graph_componentExtensionsExtensionsCompute graph components aggregate arrays component graphs math vectors graph_component Functions and aggregatesFunctions and aggregates · Extensions graph_dbExtensionsExtensionsA PostgreSQL extension for graph-database usage graph_db FeaturesFeatures · Extensions GREATESTSQL CommandsPG189.18.4. GREATEST and LEAST # GREATEST(value [, ...]) LEAST(value [, ...]) The GREATEST and LEAST functions select the largest or smallest value from a list of any number of expressions. The …Conditional Expressions › GREATEST and LEAST GREATESTFunctionsReferenceGREATEST Conditional Expressions 10 GREATEST(value [, ...]) 11 12 13 14 15 16 17 18 19 20 9.0 9.1 9.2 9.3 9.4 9.5 9.6Functions · Conditional Expressions GREATEST and LEASTManual ChaptersPG189.18.4. GREATEST and LEAST GREATEST(value [, ...]) LEAST(value [, ...]) The GREATEST and LEAST functions select the largest or smallest value from a list of any number of expressions. The ex…GREATEST and LEAST greenplum_fdwExtensionsExtensionsForeign data wrapper for querying Greenplum from PostgreSQL using SERIALIZABLE remote transactions. fdw greenplum mpp postgres-fdw greenplum_fdw Foreign data wrappersForeign data wrappers · Extensions griddb_fdwExtensionsExtensionsGridDB Foreign Data Wrapper for PostgreSQL fdw foreign-data-wrapper griddb griddb_fdw Foreign data wrappersForeign data wrappers · Extensions GROUP BYSQL CommandsPG187.2.3. The GROUP BY and HAVING Clauses # After passing the WHERE filter, the derived input table might be subject to grouping, using the GROUP BY clause, and elimination of group rows using …Table Expressions › The GROUP BY and HAVING Clauses GROUP BY ClauseManual ChaptersPG18GROUP BY Clause The optional GROUP BY clause has the general form GROUP BY [ ALL | DISTINCT ] grouping_element [, ...] GROUP BY will condense into a single row all selected rows that share t…GROUP BY Clause GROUPINGSQL CommandsPG18GROUPING ( group_by_expression(s) ) → integer Returns a bit mask indicating which GROUP BY expressions are not included in the current grouping set. Bits are assigned with the rightmost argu…Aggregate Functions GROUPINGFunctionsReferenceGROUPING Aggregate Functions 10 Integer bit mask indicating which arguments are not being included in the current grouping set GROUPING ( args... ) → integer Integer bit mask indicating whic…Functions · Aggregate Functions