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autoincExtensionsExtensionsfunctions for autoincrementing fields autoinc Functions and aggregatesFunctions and aggregates · Extensions autoinc — Functions for Autoincrementing FieldsManual ChaptersPG18F.41.2. autoinc — Functions for Autoincrementing Fields autoinc() is a trigger that stores the next value of a sequence into an integer field. This has some overlap with the built-in “serial…autoinc — Functions for Autoincrementing Fields Automatic Character Set Conversion Between Server and ClientManual ChaptersPG1823.3.3. Automatic Character Set Conversion Between Server and Client PostgreSQL supports automatic character set conversion between server and client for many combinations of character sets …Automatic Character Set Conversion Between Server and Client Automatic Creation of Array TypesManual ChaptersPG1868.2.4. Automatic Creation of Array Types Most scalar data types should have a corresponding array type (that is, a standard varlena array type whose element type is the scalar type, and whi…Automatic Creation of Array Types Automatic VacuumingManual ChaptersPG1819.10.1. Automatic Vacuuming These settings control the behavior of the autovacuum feature. Refer to Section 24.1.6 for more information. Note that many of these settings can be overridden o…Automatic Vacuuming automergeExtensionsExtensionsCRDT support in Postgres (experimental) crdt postgres automerge Data typesData types · Extensions autopexExtensionsExtensionsEvent-trigger extension that invokes Pex to automatically download and build PostgreSQL extensions when CREATE EXTENSION is run. event-trigger extension-management pex autopex AdministrationAdministration · Extensions autoreindexExtensionsExtensionsShared-preload background-worker extension that scans for bloated indexes and performs concurrent reindexing work in the background. background-worker maintenance reindex autoreindex Adminis…Administration · Extensions autovacuumConfigurationReferenceautovacuum Vacuuming 10 Controls whether the server should run the autovacuum launcher daemon. This is on by default; however, track_counts must also be enabled for autovacuum to work. This …Configuration · Vacuuming AutovacuumWait EventsReferenceAutovacuum LWLock 10 Autovacuum worker or launcher waiting to update or read the current state of autovacuum workers. 11 12 13 Waiting to read or update the current state of autovacuum worke…Wait Events · LWLock autovacuum_analyze_scale_factorConfigurationReferenceautovacuum_analyze_scale_factor Vacuuming 10 Specifies a fraction of the table size to add to autovacuum_analyze_threshold when deciding whether to trigger an ANALYZE. The default is 0.1 (10…Configuration · Vacuuming autovacuum_analyze_score_weightConfigurationReferenceautovacuum_analyze_score_weight Vacuuming 19 Specifies the scaling factor of the analyze threshold component of the score used by autovacuum for prioritization purposes. The default is 1.0. …Configuration · Vacuuming autovacuum_analyze_thresholdConfigurationReferenceautovacuum_analyze_threshold Vacuuming 10 Specifies the minimum number of inserted, updated or deleted tuples needed to trigger an ANALYZE in any one table. The default is 50 tuples. This pa…Configuration · Vacuuming autovacuum_freeze_max_ageConfigurationReferenceautovacuum_freeze_max_age Vacuuming 10 Specifies the maximum age (in transactions) that a table's pg_class.relfrozenxid field can attain before a VACUUM operation is forced to prevent transa…Configuration · Vacuuming autovacuum_freeze_score_weightConfigurationReferenceautovacuum_freeze_score_weight Vacuuming 19 Specifies the scaling factor of the transaction ID age component of the score used by autovacuum for prioritization purposes. The default is 1.0. …Configuration · Vacuuming autovacuum_informationsExtensionsExtensionsPostgreSQL extension that adds functions for reporting the autovacuum launcher PID and autovacuum worker information. autovacuum monitoring autovacuum_informations MonitoringMonitoring · Extensions autovacuum_max_parallel_workersConfigurationReferenceautovacuum_max_parallel_workers Vacuuming 19 Sets the maximum number of parallel workers that can be used by a single autovacuum worker to process indexes. This limit applies specifically to…Configuration · Vacuuming autovacuum_max_workersConfigurationReferenceautovacuum_max_workers Vacuuming 10 Specifies the maximum number of autovacuum processes (other than the autovacuum launcher) that may be running at any one time. The default is three. This …Configuration · Vacuuming autovacuum_multixact_freeze_max_ageConfigurationReferenceautovacuum_multixact_freeze_max_age Vacuuming 10 Specifies the maximum age (in multixacts) that a table's pg_class.relminmxid field can attain before a VACUUM operation is forced to prevent …Configuration · Vacuuming autovacuum_multixact_freeze_score_weightConfigurationReferenceautovacuum_multixact_freeze_score_weight Vacuuming 19 Specifies the scaling factor of the multixact ID age component of the score used by autovacuum for prioritization purposes. The default …Configuration · Vacuuming autovacuum_naptimeConfigurationReferenceautovacuum_naptime Vacuuming 10 Specifies the minimum delay between autovacuum runs on any given database. In each round the daemon examines the database and issues VACUUM and ANALYZE comman…Configuration · Vacuuming autovacuum_vacuum_cost_delayConfigurationReferenceautovacuum_vacuum_cost_delay Vacuuming 10 Specifies the cost delay value that will be used in automatic VACUUM operations. If -1 is specified, the regular vacuum_cost_delay value will be use…Configuration · Vacuuming autovacuum_vacuum_cost_limitConfigurationReferenceautovacuum_vacuum_cost_limit Vacuuming 10 Specifies the cost limit value that will be used in automatic VACUUM operations. If -1 is specified (which is the default), the regular vacuum_cost_…Configuration · Vacuuming autovacuum_vacuum_insert_scale_factorConfigurationReferenceautovacuum_vacuum_insert_scale_factor Vacuuming 13 Specifies a fraction of the table size to add to autovacuum_vacuum_insert_threshold when deciding whether to trigger a VACUUM. The default …Configuration · Vacuuming autovacuum_vacuum_insert_score_weightConfigurationReferenceautovacuum_vacuum_insert_score_weight Vacuuming 19 Specifies the scaling factor of the vacuum insert threshold component of the score used by autovacuum for prioritization purposes. The defa…Configuration · Vacuuming autovacuum_vacuum_insert_thresholdConfigurationReferenceautovacuum_vacuum_insert_threshold Vacuuming 13 Specifies the number of inserted tuples needed to trigger a VACUUM in any one table. The default is 1000 tuples. If -1 is specified, autovacuu…Configuration · Vacuuming autovacuum_vacuum_max_thresholdConfigurationReferenceautovacuum_vacuum_max_threshold Vacuuming 18 Specifies the maximum number of updated or deleted tuples needed to trigger a VACUUM in any one table, i.e., a limit on the value calculated with…Configuration · Vacuuming autovacuum_vacuum_scale_factorConfigurationReferenceautovacuum_vacuum_scale_factor Vacuuming 10 Specifies a fraction of the table size to add to autovacuum_vacuum_threshold when deciding whether to trigger a VACUUM. The default is 0.2 (20% of…Configuration · Vacuuming autovacuum_vacuum_score_weightConfigurationReferenceautovacuum_vacuum_score_weight Vacuuming 19 Specifies the scaling factor of the vacuum threshold component of the score used by autovacuum for prioritization purposes. The default is 1.0. Th…Configuration · Vacuuming autovacuum_vacuum_thresholdConfigurationReferenceautovacuum_vacuum_threshold Vacuuming 10 Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can o…Configuration · Vacuuming autovacuum_work_memConfigurationReferenceautovacuum_work_mem Resource Usage 10 Specifies the maximum amount of memory to be used by each autovacuum worker process. It defaults to -1, indicating that the value of maintenance_work_me…Configuration · Resource Usage autovacuum_worker_slotsConfigurationReferenceautovacuum_worker_slots Vacuuming 18 Specifies the number of backend slots to reserve for autovacuum worker processes. The default is typically 16 slots, but might be less if your kernel set…Configuration · Vacuuming AutovacuumMainWait EventsReferenceAutovacuumMain Activity 10 Waiting in main loop of autovacuum launcher process. 11 12 13 14 15 16 17 18 19 20 This is normally expected idleness for the matching background process. Investig…Wait Events · Activity AutovacuumScheduleWait EventsReferenceAutovacuumSchedule LWLock 10 Waiting to ensure that the table it has selected for a vacuum still needs vacuuming. 11 12 13 Waiting to ensure that a table selected for autovacuum still needs …Wait Events · LWLock aux_mysqlExtensionsExtensionsMySQL Supplementary Extension fork mysql openhalo CompatibilityCompatibility · Extensions Available Character Set ConversionsManual ChaptersPG1823.3.4. Available Character Set Conversions PostgreSQL allows conversion between any two character sets for which a conversion function is listed in the pg_conversion system catalog. Postgre…Available Character Set Conversions avalsFunctionsPG18avals ( hstore ) → text[] Extracts an hstore's values as an array. avals('a=>1,b=>2') → {1,2}hstore — hstore key/value datatype › hstore Operators and Functions avgFunctionsReferenceavg Aggregate Functions 10 the average (arithmetic mean) of all non-null input values avg ( expression ) → numeric for any integer-type argument, double precision for a floating-point argume…Functions · Aggregate Functions avocadoExtensionsExtensionsAvocadoDB PostgreSQL extension for deterministic context compilation for AI agents. ai embeddings pgrx rag vector avocado AI and vectorsAI and vectors · Extensions aws_commonsExtensionsExtensionsCommon helper objects used by Amazon RDS/Aurora PostgreSQL AWS extensions. aws helpers rds aws_commons UtilitiesUtilities · Extensions