Search PostgreSQL documentation

AioIoCompletionWait EventsReferenceAioIoCompletion IO 18 Waiting for another process to complete IO. 19 20 The wait is normal when the workload is expected to perform this read, write, sync, allocation, or completion operatio…Wait Events · IO AioIoUringExecutionWait EventsReferenceAioIoUringExecution IO 18 Waiting for IO execution via io_uring. 19 20 The wait is normal when the workload is expected to perform this read, write, sync, allocation, or completion operation…Wait Events · IO AioIoUringSubmitWait EventsReferenceAioIoUringSubmit IO 18 Waiting for IO submission via io_uring. 19 20 The wait is normal when the workload is expected to perform this read, write, sync, allocation, or completion operation a…Wait Events · IO AioUringCompletionWait EventsReferenceAioUringCompletion LWLock 18 Waiting for another process to complete IO via io_uring. 19 20 A brief sample is normal around short internal critical sections. Investigate when the same tranch…Wait Events · LWLock AioWorkerControlWait EventsReferenceAioWorkerControl LWLock 19 Waiting to update AIO worker information. 20Wait Events · LWLock AioWorkerSubmissionQueueWait EventsReferenceAioWorkerSubmissionQueue LWLock 18 Waiting to access AIO worker submission queue. 19 20 A brief sample is normal around short internal critical sections. Investigate when the same tranche af…Wait Events · LWLock aiven_extrasExtensionsExtensionsAiven PostgreSQL extras for non-superuser access to selected database features. aiven replication security aiven_extras SecuritySecurity · Extensions ajboolExtensionsExtensionsThree-valued boolean type with a pseudo-NULL unknown state for primary keys. boolean type ajbool Data typesData types · Extensions ajversionExtensionsExtensionsSemantic version type for PostgreSQL backed by compact integer storage. type version ajversion Data typesData types · Extensions akeysFunctionsPG18akeys ( hstore ) → text[] Extracts an hstore's keys as an array. akeys('a=>1,b=>2') → {a,b}hstore — hstore key/value datatype › hstore Operators and Functions alex_gist_int8ExtensionsExtensionsGiST index support for common PostgreSQL data types. alex_gist_int8 FeaturesFeatures · Extensions ALIASManual ChaptersPG1841.3.2. ALIAS newname ALIAS FOR oldname; The ALIAS syntax is more general than is suggested in the previous section: you can declare an alias for any variable, not just function parameters. …ALIAS ALLSQL CommandsPG189.25.4. ALL (array) # expression operator ALL (array expression) The right-hand side is a parenthesized expression, which must yield an array value. The left-hand expression is evaluated and…Row and Array Comparisons › ALL (array) ALLManual ChaptersPG189.24.5. ALL expression operator ALL (subquery) The right-hand side is a parenthesized subquery, which must return exactly one column. The left-hand expression is evaluated and compared to ea…ALL ALL (array)Manual ChaptersPG189.25.4. ALL (array) expression operator ALL (array expression) The right-hand side is a parenthesized expression, which must yield an array value. The left-hand expression is evaluated and c…ALL (array) all_hooksExtensionsExtensionsExtension for PostgreSQL emitting a message for each of all available hooks all_hooks FeaturesFeatures · Extensions all_in_one_libExtensionsExtensionsRust/pgrx utility extension with encryption helpers and a sample FDW wrapper. encryption fdw pgrx all_in_one_lib UtilitiesUtilities · Extensions all_substrings_tokenizerExtensionsExtensionsTokenizes text to all substrings bigger than a fixed character length. text tokenizer all_substrings_tokenizer Full-text searchFull-text search · Extensions ALLOCATE DESCRIPTORManual ChaptersPG18ALLOCATE DESCRIPTOR ALLOCATE DESCRIPTOR — allocate an SQL descriptor area Synopsis ALLOCATE DESCRIPTOR nameALLOCATE DESCRIPTOR allow_alter_systemConfigurationReferenceallow_alter_system Version and Platform Compatibility 17 When allow_alter_system is set to off, an error is returned if the ALTER SYSTEM command is executed. This parameter can only be set i…Configuration · Version and Platform Compatibility allow_in_place_tablespacesConfigurationReferenceallow_in_place_tablespaces Developer Options 10 Allows tablespaces to be created as directories inside pg_tblspc, when an empty location string is provided to the CREATE TABLESPACE command. …Configuration · Developer Options allow_system_table_modsConfigurationReferenceallow_system_table_mods Developer Options 10 Allows modification of the structure of system tables. This is used by initdb. This parameter can only be set at server start. 11 12 13 Allows mo…Configuration · Developer Options alloydb_scannExtensionsExtensionsAlloyDB ScaNN extension for approximate nearest-neighbor vector indexes. alloydb ann scann vector alloydb_scann AI and vectorsAI and vectors · Extensions alohadb_approxExtensionsExtensionsApproximate query processing: HLL, Count-Min Sketch, Top-K alohadb_approx Functions and aggregatesFunctions and aggregates · Extensions alohadb_branchExtensionsExtensionsLightweight database branching for testing migrations and experiments alohadb_branch FeaturesFeatures · Extensions alohadb_nl2sqlExtensionsExtensionsNatural language to SQL translation via LLM API alohadb_nl2sql AI and vectorsAI and vectors · Extensions alohadb_poolExtensionsExtensionsAlohaDB Built-in Connection Pooling alohadb_pool AdministrationAdministration · Extensions alohadb_query_storeExtensionsExtensionsAlohaDB Query Store and Index Advisor alohadb_query_store MonitoringMonitoring · Extensions alohadb_scaleExtensionsExtensionsAlohaDB Scale - scale-to-zero management alohadb_scale AdministrationAdministration · Extensions alohadb_timeseriesExtensionsExtensionsAuto-partition management for time-series tables using a background worker alohadb_timeseries Time seriesTime series · Extensions ALTER AGGREGATEManual ChaptersPG18ALTER AGGREGATE ALTER AGGREGATE — change the definition of an aggregate function Synopsis ALTER AGGREGATE name ( aggregate_signature ) RENAME TO new_name ALTER AGGREGATE name ( aggregate_sig…ALTER AGGREGATE ALTER AGGREGATESQL CommandsReferenceALTER AGGREGATE Functions & Procedures 10 change the definition of an aggregate function ALTER AGGREGATE name ( aggregate_signature ) RENAME TO new_name ALTER AGGREGATE name ( aggregate_sign…SQL Commands · Functions & Procedures ALTER COLLATIONManual ChaptersPG18ALTER COLLATION ALTER COLLATION — change the definition of a collation Synopsis ALTER COLLATION name REFRESH VERSION ALTER COLLATION name RENAME TO new_name ALTER COLLATION name OWNER TO { n…ALTER COLLATION ALTER COLLATIONSQL CommandsReferenceALTER COLLATION Types & Operators 10 change the definition of a collation ALTER COLLATION name REFRESH VERSION ALTER COLLATION name RENAME TO new_name ALTER COLLATION name OWNER TO { new_ow…SQL Commands · Types & Operators ALTER CONVERSIONManual ChaptersPG18ALTER CONVERSION ALTER CONVERSION — change the definition of a conversion Synopsis ALTER CONVERSION name RENAME TO new_name ALTER CONVERSION name OWNER TO { new_owner | CURRENT_ROLE | CURREN…ALTER CONVERSION ALTER CONVERSIONSQL CommandsReferenceALTER CONVERSION Types & Operators 10 change the definition of a conversion ALTER CONVERSION name RENAME TO new_name ALTER CONVERSION name OWNER TO { new_owner | CURRENT_USER | SESSION_USER …SQL Commands · Types & Operators ALTER DATABASEManual ChaptersPG18ALTER DATABASE ALTER DATABASE — change a database Synopsis ALTER DATABASE name [ [ WITH ] option [ ... ] ] where option can be: ALLOW_CONNECTIONS allowconn CONNECTION LIMIT connlimit IS_TEMP…ALTER DATABASE ALTER DATABASESQL CommandsReferenceALTER DATABASE Databases & Schemas 10 change a database ALTER DATABASE name [ [ WITH ] option [ ... ] ] where option can be: ALLOW_CONNECTIONS allowconn CONNECTION LIMIT connlimit IS_TEMPL…SQL Commands · Databases & Schemas ALTER DEFAULT PRIVILEGESManual ChaptersPG18ALTER DEFAULT PRIVILEGES ALTER DEFAULT PRIVILEGES — define default access privileges Synopsis ALTER DEFAULT PRIVILEGES [ FOR { ROLE | USER } target_role [, ...] ] [ IN SCHEMA schema_name [, …ALTER DEFAULT PRIVILEGES ALTER DEFAULT PRIVILEGESSQL CommandsReferenceALTER DEFAULT PRIVILEGES Roles & Privileges 10 define default access privileges ALTER DEFAULT PRIVILEGES [ FOR { ROLE | USER } target_role [, ...] ] [ IN SCHEMA schema_name [, ...] ] abbrevi…SQL Commands · Roles & Privileges