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enable_nestloopConfigurationReferenceenable_nestloop Query Tuning 10 Enables or disables the query planner's use of nested-loop join plans. It is impossible to suppress nested-loop joins entirely, but turning this variable off …Configuration · Query Tuning enable_parallel_appendConfigurationReferenceenable_parallel_append Query Tuning 11 Enables or disables the query planner's use of parallel-aware append plan types. The default is on. 12 13 14 15 16 17 18 19 20 enable_parallel_append c…Configuration · Query Tuning enable_parallel_hashConfigurationReferenceenable_parallel_hash Query Tuning 11 Enables or disables the query planner's use of hash-join plan types with parallel hash. Has no effect if hash-join plans are not also enabled. The defaul…Configuration · Query Tuning enable_partition_pruningConfigurationReferenceenable_partition_pruning Query Tuning 11 Enables or disables the query planner's ability to eliminate a partitioned table's partitions from query plans. This also controls the planner's abil…Configuration · Query Tuning enable_partitionwise_aggregateConfigurationReferenceenable_partitionwise_aggregate Query Tuning 11 Enables or disables the query planner's use of partitionwise grouping or aggregation, which allows grouping or aggregation on partitioned table…Configuration · Query Tuning enable_partitionwise_joinConfigurationReferenceenable_partitionwise_join Query Tuning 11 Enables or disables the query planner's use of partitionwise join, which allows a join between partitioned tables to be performed by joining the mat…Configuration · Query Tuning enable_presorted_aggregateConfigurationReferenceenable_presorted_aggregate Query Tuning 16 Controls if the query planner will produce a plan which will provide rows which are presorted in the order required for the query's ORDER BY / DIST…Configuration · Query Tuning enable_self_join_eliminationConfigurationReferenceenable_self_join_elimination Query Tuning 18 Enables or disables the query planner's optimization which analyses the query tree and replaces self joins with semantically equivalent single sc…Configuration · Query Tuning enable_seqscanConfigurationReferenceenable_seqscan Query Tuning 10 Enables or disables the query planner's use of sequential scan plan types. It is impossible to suppress sequential scans entirely, but turning this variable of…Configuration · Query Tuning enable_sortConfigurationReferenceenable_sort Query Tuning 10 Enables or disables the query planner's use of explicit sort steps. It is impossible to suppress explicit sorts entirely, but turning this variable off discourage…Configuration · Query Tuning enable_tidscanConfigurationReferenceenable_tidscan Query Tuning 10 Enables or disables the query planner's use of TID scan plan types. The default is on. 11 12 13 14 15 16 17 18 19 20 9.0 9.1 9.2 9.3 9.4 9.5 9.6 enable_tidscan…Configuration · Query Tuning escape_string_warningConfigurationReferenceescape_string_warning Version and Platform Compatibility 10 When on, a warning is issued if a backslash (\) appears in an ordinary string literal ('...' syntax) and standard_conforming_strin…Configuration · Version and Platform Compatibility event_sourceConfigurationReferenceevent_source Reporting and Logging 10 When logging to event log is enabled, this parameter determines the program name used to identify PostgreSQL messages in the log. The default is Postgre…Configuration · Reporting and Logging event_triggersConfigurationReferenceevent_triggers Client Connection Defaults 17 Allow temporarily disabling execution of event triggers in order to troubleshoot and repair faulty event triggers. All event triggers will be dis…Configuration · Client Connection Defaults exit_on_errorConfigurationReferenceexit_on_error Error Handling 10 If true, any error will terminate the current session. By default, this is set to false, so that only FATAL errors will terminate the session. 11 12 If on, an…Configuration · Error Handling extension_control_pathConfigurationReferenceextension_control_path Client Connection Defaults 18 A path to search for extensions, specifically extension control files (name.control). The remaining extension script and secondary contro…Configuration · Client Connection Defaults extension_destdirConfigurationReferenceextension_destdir File Locations 10 11 12 13 14 15 16 17 9.5 9.6 The version matrix proves that extension_destdir is exposed by the measured Debian/PGDG binaries from PG9.5 through PG17. An …Configuration · File Locations external_pid_fileConfigurationReferenceexternal_pid_file File Locations 10 Specifies the name of an additional process-ID (PID) file that the server should create for use by server administration programs. This parameter can only…Configuration · File Locations extra_float_digitsConfigurationReferenceextra_float_digits Client Connection Defaults 10 This parameter adjusts the number of digits displayed for floating-point values, including float4, float8, and geometric data types. The para…Configuration · Client Connection Defaults file_copy_methodConfigurationReferencefile_copy_method Resource Usage 18 Specifies the method used to copy files. Possible values are COPY (default) and CLONE (if operating support is available). This parameter affects: CREATE D…Configuration · Resource Usage file_extend_methodConfigurationReferencefile_extend_method Resource Usage 16 Specifies the method used to extend data files during bulk operations such as COPY. The first available option is used as the default, depending on the o…Configuration · Resource Usage force_parallel_modeConfigurationReferenceforce_parallel_mode Developer Options 10 Allows the use of parallel queries for testing purposes even in cases where no performance benefit is expected. The allowed values of force_parallel_…Configuration · Developer Options from_collapse_limitConfigurationReferencefrom_collapse_limit Query Tuning 10 The planner will merge sub-queries into upper queries if the resulting FROM list would have no more than this many items. Smaller values reduce planning t…Configuration · Query Tuning fsyncConfigurationReferencefsync Write-Ahead Log 10 If this parameter is on, the PostgreSQL server will try to make sure that updates are physically written to disk, by issuing fsync() system calls or various equivale…Configuration · Write-Ahead Log full_page_writesConfigurationReferencefull_page_writes Write-Ahead Log 10 When this parameter is on, the PostgreSQL server writes the entire content of each disk page to WAL during the first modification of that page after a che…Configuration · Write-Ahead Log geqoConfigurationReferencegeqo Query Tuning 10 Enables or disables genetic query optimization. This is on by default. It is usually best not to turn it off in production; the geqo_threshold variable provides more gra…Configuration · Query Tuning geqo_effortConfigurationReferencegeqo_effort Query Tuning 10 Controls the trade-off between planning time and query plan quality in GEQO. This variable must be an integer in the range from 1 to 10. The default value is five…Configuration · Query Tuning geqo_generationsConfigurationReferencegeqo_generations Query Tuning 10 Controls the number of generations used by GEQO, that is the number of iterations of the algorithm. It must be at least one, and useful values are in the sam…Configuration · Query Tuning geqo_pool_sizeConfigurationReferencegeqo_pool_size Query Tuning 10 Controls the pool size used by GEQO, that is the number of individuals in the genetic population. It must be at least two, and useful values are typically 100 …Configuration · Query Tuning geqo_seedConfigurationReferencegeqo_seed Query Tuning 10 Controls the initial value of the random number generator used by GEQO to select random paths through the join order search space. The value can range from zero (th…Configuration · Query Tuning geqo_selection_biasConfigurationReferencegeqo_selection_bias Query Tuning 10 Controls the selection bias used by GEQO. The selection bias is the selective pressure within the population. Values can be from 1.50 to 2.00; the latter …Configuration · Query Tuning geqo_thresholdConfigurationReferencegeqo_threshold Query Tuning 10 Use genetic query optimization to plan queries with at least this many FROM items involved. (Note that a FULL OUTER JOIN construct counts as only one FROM item…Configuration · Query Tuning gin_fuzzy_search_limitConfigurationReferencegin_fuzzy_search_limit Client Connection Defaults 10 Soft upper limit of the size of the set returned by GIN index scans. For more information see Section 64.5. 11 Soft upper limit of the si…Configuration · Client Connection Defaults gin_pending_list_limitConfigurationReferencegin_pending_list_limit Client Connection Defaults 10 Sets the maximum size of the GIN pending list which is used when fastupdate is enabled. If the list grows larger than this maximum size, …Configuration · Client Connection Defaults gss_accept_delegationConfigurationReferencegss_accept_delegation Connections and Authentication 16 Sets whether GSSAPI delegation should be accepted from the client. The default is off meaning credentials from the client will not be …Configuration · Connections and Authentication hash_mem_multiplierConfigurationReferencehash_mem_multiplier Resource Usage 13 Used to compute the maximum amount of memory that hash-based operations can use. The final limit is determined by multiplying work_mem by hash_mem_multi…Configuration · Resource Usage hba_fileConfigurationReferencehba_file File Locations 10 Specifies the configuration file for host-based authentication (customarily called pg_hba.conf). This parameter can only be set at server start. 11 12 13 14 15 16 …Configuration · File Locations hosts_fileConfigurationReferencehosts_file File Locations 19 Specifies the configuration file for host-based SSL configuration (customarily called pg_hosts.conf). This parameter can only be set at server start. See also Se…Configuration · File Locations hot_standbyConfigurationReferencehot_standby Replication 10 Specifies whether or not you can connect and run queries during recovery, as described in Section 26.5. The default value is on. This parameter can only be set at …Configuration · Replication hot_standby_feedbackConfigurationReferencehot_standby_feedback Replication 10 Specifies whether or not a hot standby will send feedback to the primary or upstream standby about queries currently executing on the standby. This parame…Configuration · Replication