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Mapping Tables to XMLManual ChaptersPG189.15.4. Mapping Tables to XML The following functions map the contents of relational tables to XML values. They can be thought of as XML export functionality: table_to_xml ( table regclass, …Mapping Tables to XML Mappings between SQL and XML Data Types and ValuesManual ChaptersPG18D.3.1.3. Mappings between SQL and XML Data Types and Values In SQL:2006 and later, both directions of conversion between standard SQL data types and the XML Schema types are specified precis…Mappings between SQL and XML Data Types and Values martindonadieu-supabase_auth_adminExtensionsExtensionsSupabase Auth tool to check if a user is an platform admin database.dev tle martindonadieu-supabase_auth_admin SecuritySecurity · Extensions masklenFunctionsReferencemasklen Network Address Functions And Operators 10 extract netmask length masklen ( inet ) → int extract netmask length 11 12 13 Returns the netmask length in bits. masklen ( inet ) → intege…Functions · Network Address Functions And Operators mastermobilitydbExtensionsExtensionsSchema, types, and utilities for managing moving-object trajectories with MobilityDB. mastermobilitydb GeospatialGeospatial · Extensions Materialized ViewsManual ChaptersPG1839.3. Materialized Views Materialized views in PostgreSQL use the rule system like views do, but persist the results in a table-like form. The main differences between: CREATE MATERIALIZED V…Materialized Views Mathematical Functions and OperatorsManual ChaptersPG189.3. Mathematical Functions and Operators Mathematical operators are provided for many PostgreSQL types. For types without standard mathematical conventions (e.g., date/time types) we descri…Mathematical Functions and Operators maxFunctionsReferencemax Aggregate Functions 10 maximum value of expression across all non-null input values max ( expression ) → same as argument type maximum value of expression across all non-null input value…Functions · Aggregate Functions max_active_replication_originsConfigurationReferencemax_active_replication_origins Replication 18 Specifies how many replication origins (see Chapter 48) can be tracked simultaneously, effectively limiting how many logical replication subscri…Configuration · Replication max_connectionsConfigurationReferencemax_connections Connections and Authentication 10 Determines the maximum number of concurrent connections to the database server. The default is typically 100 connections, but might be less …Configuration · Connections and Authentication max_files_per_processConfigurationReferencemax_files_per_process Resource Usage 10 Sets the maximum number of simultaneously open files allowed to each server subprocess. The default is one thousand files. If the kernel is enforcing …Configuration · Resource Usage max_function_argsConfigurationReferencemax_function_args Preset Options 10 Reports the maximum number of function arguments. It is determined by the value of FUNC_MAX_ARGS when building the server. The default value is 100 argume…Configuration · Preset Options max_identifier_lengthConfigurationReferencemax_identifier_length Preset Options 10 Reports the maximum identifier length. It is determined as one less than the value of NAMEDATALEN when building the server. The default value of NAMED…Configuration · Preset Options max_index_keysConfigurationReferencemax_index_keys Preset Options 10 Reports the maximum number of index keys. It is determined by the value of INDEX_MAX_KEYS when building the server. The default value is 32 keys. 11 12 13 14…Configuration · Preset Options max_locks_per_transactionConfigurationReferencemax_locks_per_transaction Lock Management 10 The shared lock table tracks locks on max_locks_per_transaction * (max_connections + max_prepared_transactions) objects (e.g., tables); hence, no…Configuration · Lock Management max_logical_replication_workersConfigurationReferencemax_logical_replication_workers Replication 10 Specifies maximum number of logical replication workers. This includes both apply workers and table synchronization workers. Logical replicatio…Configuration · Replication max_notify_queue_pagesConfigurationReferencemax_notify_queue_pages Resource Usage 17 Specifies the maximum amount of allocated pages for NOTIFY / LISTEN queue. The default value is 1048576. For 8 KB pages it allows to consume up to 8 …Configuration · Resource Usage max_parallel_apply_workers_per_subscriptionConfigurationReferencemax_parallel_apply_workers_per_subscription Replication 16 Maximum number of parallel apply workers per subscription. This parameter controls the amount of parallelism for streaming of in-pr…Configuration · Replication max_parallel_maintenance_workersConfigurationReferencemax_parallel_maintenance_workers Resource Usage 11 Sets the maximum number of parallel workers that can be started by a single utility command. Currently, the only parallel utility command t…Configuration · Resource Usage max_parallel_workersConfigurationReferencemax_parallel_workers Resource Usage 10 Sets the maximum number of workers that the system can support for parallel queries. The default value is 8. When increasing or decreasing this value, …Configuration · Resource Usage max_parallel_workers_per_gatherConfigurationReferencemax_parallel_workers_per_gather Resource Usage 10 Sets the maximum number of workers that can be started by a single Gather or Gather Merge node. Parallel workers are taken from the pool of …Configuration · Resource Usage max_pred_locks_per_pageConfigurationReferencemax_pred_locks_per_page Lock Management 10 This controls how many rows on a single page can be predicate-locked before the lock is promoted to covering the whole page. The default is 2. This…Configuration · Lock Management max_pred_locks_per_relationConfigurationReferencemax_pred_locks_per_relation Lock Management 10 This controls how many pages or tuples of a single relation can be predicate-locked before the lock is promoted to covering the whole relation.…Configuration · Lock Management max_pred_locks_per_transactionConfigurationReferencemax_pred_locks_per_transaction Lock Management 10 The shared predicate lock table tracks locks on max_pred_locks_per_transaction * (max_connections + max_prepared_transactions) objects (e.g.…Configuration · Lock Management max_prepared_transactionsConfigurationReferencemax_prepared_transactions Resource Usage 10 Sets the maximum number of transactions that can be in the “prepared” state simultaneously (see PREPARE TRANSACTION). Setting this parameter to ze…Configuration · Resource Usage max_protocol_versionCommand-line ToolsPG18max_protocol_version Specifies the protocol version to request from the server. The default is to use version 3.0 of the PostgreSQL protocol, unless the connection string specifies a feature…Database Connection Control Functions › Parameter Key Words max_repack_replication_slotsConfigurationReferencemax_repack_replication_slots Replication 19 Specifies the maximum number of replication slots for use of the REPACK command. The default is 5. This parameter can only be set at server start.…Configuration · Replication max_replication_slotsConfigurationReferencemax_replication_slots Replication 10 Specifies the maximum number of replication slots (see Section 26.2.6) that the server can support. The default is 10. This parameter can only be set at …Configuration · Replication max_slot_wal_keep_sizeConfigurationReferencemax_slot_wal_keep_size Replication 13 Specify the maximum size of WAL files that replication slots are allowed to retain in the pg_wal directory at checkpoint time. If max_slot_wal_keep_size…Configuration · Replication max_stack_depthConfigurationReferencemax_stack_depth Resource Usage 10 Specifies the maximum safe depth of the server's execution stack. The ideal setting for this parameter is the actual stack size limit enforced by the kernel…Configuration · Resource Usage max_standby_archive_delayConfigurationReferencemax_standby_archive_delay Replication 10 When Hot Standby is active, this parameter determines how long the standby server should wait before canceling standby queries that conflict with abo…Configuration · Replication max_standby_streaming_delayConfigurationReferencemax_standby_streaming_delay Replication 10 When Hot Standby is active, this parameter determines how long the standby server should wait before canceling standby queries that conflict with a…Configuration · Replication max_sync_workers_per_subscriptionConfigurationReferencemax_sync_workers_per_subscription Replication 10 Maximum number of synchronization workers per subscription. This parameter controls the amount of parallelism of the initial data copy during…Configuration · Replication max_wal_sendersConfigurationReferencemax_wal_senders Replication 10 Specifies the maximum number of concurrent connections from standby servers or streaming base backup clients (i.e., the maximum number of simultaneously runnin…Configuration · Replication max_wal_sizeConfigurationReferencemax_wal_size Write-Ahead Log 10 Maximum size to let the WAL grow during automatic checkpoints. This is a soft limit; WAL size can exceed max_wal_size under special circumstances, like under …Configuration · Write-Ahead Log max_worker_processesConfigurationReferencemax_worker_processes Resource Usage 10 Sets the maximum number of background processes that the system can support. This parameter can only be set at server start. The default is 8. When run…Configuration · Resource Usage mbusExtensionsExtensionssimple message bus for pg mbus FeaturesFeatures · Extensions mcp_postgrestExtensionsExtensionsPostgreSQL extension to define AI tools compatible with Anthropic's Model Context Protocol (MCP). Fully customizable, schema-agnostic, secure, and integrated with PostgREST. ai mcp model-con…AI and vectors · Extensions MCV ListsManual ChaptersPG1869.2.3. MCV Lists As explained in Section 69.2.1, functional dependencies are very cheap and efficient type of statistics, but their main limitation is their global nature (only tracking dep…MCV Lists md5FunctionsReferencemd5 String Functions And Operators 10 Calculates the MD5 hash of string, returning the result in hexadecimal md5 ( string ) → text Calculates the MD5 hash of string, returning the result in …Functions · String Functions And Operators