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debug_exec_backendConfigurationReferencedebug_exec_backend Preset Options 19 Reports whether PostgreSQL has been built with EXEC_BACKEND enabled. That is the case on Windows or if the macro EXEC_BACKEND is defined when PostgreSQL …Configuration · Preset Options debug_io_directConfigurationReferencedebug_io_direct Developer Options 16 Ask the kernel to minimize caching effects for relation data and WAL files using O_DIRECT (most Unix-like systems), F_NOCACHE (macOS) or FILE_FLAG_NO_BUF…Configuration · Developer Options debug_logical_replication_streamingConfigurationReferencedebug_logical_replication_streaming Developer Options 16 The allowed values are buffered and immediate. The default is buffered. This parameter is intended to be used to test logical decodin…Configuration · Developer Options debug_parallel_queryConfigurationReferencedebug_parallel_query Developer Options 16 Allows the use of parallel queries for testing purposes even in cases where no performance benefit is expected. The allowed values of debug_parallel…Configuration · Developer Options debug_pretty_printConfigurationReferencedebug_pretty_print Reporting and Logging 10 When set, debug_pretty_print indents the messages produced by debug_print_parse, debug_print_rewritten, or debug_print_plan. This results in more …Configuration · Reporting and Logging debug_print_parseConfigurationReferencedebug_print_parse Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or the ex…Configuration · Reporting and Logging debug_print_planConfigurationReferencedebug_print_plan Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or the exe…Configuration · Reporting and Logging debug_print_raw_parseConfigurationReferencedebug_print_raw_parse Reporting and Logging 19 These parameters enable various debugging output to be emitted. When set, they print the resulting raw parse tree, the parse tree, the query re…Configuration · Reporting and Logging debug_print_rewrittenConfigurationReferencedebug_print_rewritten Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or th…Configuration · Reporting and Logging debug_raw_expression_coverage_testConfigurationReferencedebug_raw_expression_coverage_test Developer Options 18 Enabling this forces all raw parse trees for DML statements to be scanned by raw_expression_tree_walker(), to facilitate catching erro…Configuration · Developer Options debug_write_read_parse_plan_treesConfigurationReferencedebug_write_read_parse_plan_trees Developer Options 18 Enabling this forces all parse and plan trees to be passed through outfuncs.c/readfuncs.c, to facilitate catching errors and omissions …Configuration · Developer Options default_statistics_targetConfigurationReferencedefault_statistics_target Query Tuning 10 Sets the default statistics target for table columns without a column-specific target set via ALTER TABLE SET STATISTICS. Larger values increase the…Configuration · Query Tuning default_table_access_methodConfigurationReferencedefault_table_access_method Client Connection Defaults 12 This parameter specifies the default table access method to use when creating tables or materialized views if the CREATE command doe…Configuration · Client Connection Defaults default_tablespaceConfigurationReferencedefault_tablespace Client Connection Defaults 10 This variable specifies the default tablespace in which to create objects (tables and indexes) when a CREATE command does not explicitly spec…Configuration · Client Connection Defaults default_text_search_configConfigurationReferencedefault_text_search_config Client Connection Defaults 10 Selects the text search configuration that is used by those variants of the text search functions that do not have an explicit argume…Configuration · Client Connection Defaults default_toast_compressionConfigurationReferencedefault_toast_compression Client Connection Defaults 14 This variable sets the default TOAST compression method for values of compressible columns. (This can be overridden for individual col…Configuration · Client Connection Defaults default_transaction_deferrableConfigurationReferencedefault_transaction_deferrable Client Connection Defaults 10 When running at the serializable isolation level, a deferrable read-only SQL transaction may be delayed before it is allowed to p…Configuration · Client Connection Defaults default_transaction_isolationConfigurationReferencedefault_transaction_isolation Client Connection Defaults 10 Each SQL transaction has an isolation level, which can be either “read uncommitted”, “read committed”, “repeatable read”, or “seri…Configuration · Client Connection Defaults default_transaction_read_onlyConfigurationReferencedefault_transaction_read_only Client Connection Defaults 10 A read-only SQL transaction cannot alter non-temporary tables. This parameter controls the default read-only status of each new tr…Configuration · Client Connection Defaults default_with_oidsConfigurationReferencedefault_with_oids Version and Platform Compatibility 10 This controls whether CREATE TABLE and CREATE TABLE AS include an OID column in newly-created tables, if neither WITH OIDS nor WITHOUT…Configuration · Version and Platform Compatibility dynamic_library_pathConfigurationReferencedynamic_library_path Client Connection Defaults 10 If a dynamically loadable module needs to be opened and the file name specified in the CREATE FUNCTION or LOAD command does not have a dire…Configuration · Client Connection Defaults dynamic_shared_memory_typeConfigurationReferencedynamic_shared_memory_type Resource Usage 10 Specifies the dynamic shared memory implementation that the server should use. Possible values are posix (for POSIX shared memory allocated using…Configuration · Resource Usage effective_cache_sizeConfigurationReferenceeffective_cache_size Query Tuning 10 Sets the planner's assumption about the effective size of the disk cache that is available to a single query. This is factored into estimates of the cost…Configuration · Query Tuning effective_io_concurrencyConfigurationReferenceeffective_io_concurrency Resource Usage 10 Sets the number of concurrent disk I/O operations that PostgreSQL expects can be executed simultaneously. Raising this value will increase the numb…Configuration · Resource Usage effective_wal_levelConfigurationReferenceeffective_wal_level Preset Options 19 Reports the actual WAL logging level currently in effect in the system. This parameter shares the same set of values as wal_level, but reflects the oper…Configuration · Preset Options enable_async_appendConfigurationReferenceenable_async_append Query Tuning 14 Enables or disables the query planner's use of async-aware append plan types. The default is on. 15 16 17 18 19 20 enable_async_append controls whether th…Configuration · Query Tuning enable_bitmapscanConfigurationReferenceenable_bitmapscan Query Tuning 10 Enables or disables the query planner's use of bitmap-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_b…Configuration · Query Tuning enable_distinct_reorderingConfigurationReferenceenable_distinct_reordering Query Tuning 18 Enables or disables the query planner's ability to reorder DISTINCT keys to match the input path's pathkeys. The default is on. 19 20 enable_distin…Configuration · Query Tuning enable_eager_aggregateConfigurationReferenceenable_eager_aggregate Query Tuning 19 Enables or disables the query planner's ability to partially push aggregation past a join, and finalize it once all the relations are joined. The defau…Configuration · Query Tuning enable_gathermergeConfigurationReferenceenable_gathermerge Query Tuning 10 Enables or disables the query planner's use of gather merge plan types. The default is on. 11 12 13 14 15 16 17 18 19 20 enable_gathermerge controls whethe…Configuration · Query Tuning enable_group_by_reorderingConfigurationReferenceenable_group_by_reordering Query Tuning 17 Controls if the query planner will produce a plan which will provide GROUP BY keys sorted in the order of keys of a child node of the plan, such as…Configuration · Query Tuning enable_groupaggConfigurationReferenceenable_groupagg Query Tuning 20 Enables or disables the query planner's use of sort-based grouping and aggregation plan types. The default is on.Configuration · Query Tuning enable_hashaggConfigurationReferenceenable_hashagg Query Tuning 10 Enables or disables the query planner's use of hashed aggregation 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 enab…Configuration · Query Tuning enable_hashjoinConfigurationReferenceenable_hashjoin Query Tuning 10 Enables or disables the query planner's use of hash-join 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_hashj…Configuration · Query Tuning enable_incremental_sortConfigurationReferenceenable_incremental_sort Query Tuning 13 Enables or disables the query planner's use of incremental sort steps. The default is on. 14 15 16 17 18 19 20 enable_incremental_sort controls whethe…Configuration · Query Tuning enable_indexonlyscanConfigurationReferenceenable_indexonlyscan Query Tuning 10 Enables or disables the query planner's use of index-only-scan plan types (see Section 11.11). The default is on. 11 Enables or disables the query planne…Configuration · Query Tuning enable_indexscanConfigurationReferenceenable_indexscan Query Tuning 10 Enables or disables the query planner's use of index-scan plan types. The default is on. 11 12 Enables or disables the query planner's use of index-scan and …Configuration · Query Tuning enable_materialConfigurationReferenceenable_material Query Tuning 10 Enables or disables the query planner's use of materialization. It is impossible to suppress materialization entirely, but turning this variable off prevents …Configuration · Query Tuning enable_memoizeConfigurationReferenceenable_memoize Query Tuning 14 Enables or disables the query planner's use of memoize plans for caching results from parameterized scans inside nested-loop joins. This plan type allows scans…Configuration · Query Tuning enable_mergejoinConfigurationReferenceenable_mergejoin Query Tuning 10 Enables or disables the query planner's use of merge-join 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_mer…Configuration · Query Tuning