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lo_compat_privilegesConfigurationReferencelo_compat_privileges Version and Platform Compatibility 10 In PostgreSQL releases prior to 9.0, large objects did not have access privileges and were, therefore, always readable and writable…Configuration · Version and Platform Compatibility lo_from_byteaFunctionsPG18lo_from_bytea ( loid oid, data bytea ) → oid Creates a large object and stores data in it. If loid is zero then the system will choose a free OID, otherwise that OID is used (with an error i…Server-Side Functions lo_getFunctionsPG18lo_get ( loid oid [, offset bigint, length integer ] ) → bytea Extracts the large object's contents, or a substring thereof. lo_get(24528, 0, 3) → \xffaaffServer-Side Functions lo_putFunctionsPG18lo_put ( loid oid, offset bigint, data bytea ) → void Writes data starting at the given offset within the large object; the large object is enlarged if necessary. lo_put(24528, 1, '\xaa') →Server-Side Functions LOADManual ChaptersPG18LOAD LOAD — load a shared library file Synopsis LOAD 'filename'LOAD LOADSQL CommandsReferenceLOAD Extensions & Access Methods 10 load a shared library file LOAD 'filename' This command loads a shared library file into the PostgreSQL server's address space. If the file has been loade…SQL Commands · Extensions & Access Methods load_balance_hostsCommand-line ToolsPG18load_balance_hosts Controls the order in which the client tries to connect to the available hosts and addresses. Once a connection attempt is successful no other hosts and addresses will be …Database Connection Control Functions › Parameter Key Words local_preload_librariesConfigurationReferencelocal_preload_libraries Client Connection Defaults 10 This variable specifies one or more shared libraries that are to be preloaded at connection start. It contains a comma-separated list of…Configuration · Client Connection Defaults Locale and EncodingManual ChaptersPG1831.1.4. Locale and Encoding By default, tests using a temporary installation use the locale defined in the current environment and the corresponding database encoding as determined by initdb…Locale and Encoding Locale and FormattingManual ChaptersPG1819.11.2. Locale and Formatting DateStyle (string) Sets the display format for date and time values, as well as the rules for interpreting ambiguous date input values. For historical reasons,…Locale and Formatting Locale Canonicalization and ValidationManual ChaptersPG1823.1.5.2. Locale Canonicalization and Validation When defining a new ICU collation object or database with ICU as the provider, the given locale name is transformed ("canonicalized") into a …Locale Canonicalization and Validation Locale DifferencesManual ChaptersPG1831.2.2. Locale Differences If you run the tests against a server that was initialized with a collation-order locale other than C, then there might be differences due to sort order and subseq…Locale Differences Locale ProvidersManual ChaptersPG1823.1.4. Locale Providers A locale provider specifies which library defines the locale behavior for collations and character classifications. The commands and tools that select the locale set…Locale Providers Locale SupportManual ChaptersPG1823.1. Locale Support Locale support refers to an application respecting cultural preferences regarding alphabets, sorting, number formatting, etc. PostgreSQL uses the standard ISO C and POSI…Locale Support LocalizationManual ChaptersPG18Chapter 23. Localization This chapter describes the available localization features from the point of view of the administrator. PostgreSQL supports two localization facilities: Using the lo…Localization localtimeSQL CommandsPG18localtime → time Current time of day; see Section 9.9.5 localtime → 14:39:53.662522Date/Time Functions and Operators localtimeFunctionsReferencelocaltime Date/Time Functions And Operators 10 Current time of day; see Section 9.9.4 localtime → time Current time of day; see Section 9.9.4 LOCALTIME(precision) CURRENT_TIME and CURRENT_TI…Functions · Date/Time Functions And Operators localtimestampSQL CommandsPG18localtimestamp → timestamp Current date and time (start of current transaction); see Section 9.9.5 localtimestamp → 2019-12-23 14:39:53.662522Date/Time Functions and Operators localtimestampFunctionsReferencelocaltimestamp Date/Time Functions And Operators 10 Current date and time (start of current transaction); see Section 9.9.4 localtimestamp → timestamp Current date and time (start of current…Functions · Date/Time Functions And Operators LOCKManual ChaptersPG18LOCK LOCK — lock a table Synopsis LOCK [ TABLE ] [ ONLY ] name [ * ] [, ...] [ IN lockmode MODE ] [ NOWAIT ] where lockmode is one of: ACCESS SHARE | ROW SHARE | ROW EXCLUSIVE | SHARE UPDATE…LOCK LOCKSQL CommandsReferenceLOCK Queries & Data 10 lock a table LOCK [ TABLE ] [ ONLY ] name [ * ] [, ...] [ IN lockmode MODE ] [ NOWAIT ] where lockmode is one of: ACCESS SHARE | ROW SHARE | ROW EXCLUSIVE | SHARE UP…SQL Commands · Queries & Data Lock ManagementManual ChaptersPG1819.12. Lock Management deadlock_timeout (integer) # This is the amount of time to wait on a lock before checking to see if there is a deadlock condition. The check for deadlock is relatively…Lock Management lock_timeoutConfigurationReferencelock_timeout Client Connection Defaults 10 Abort any statement that waits longer than the specified number of milliseconds while attempting to acquire a lock on a table, index, row, or other…Configuration · Client Connection Defaults LockFastPathWait EventsReferenceLockFastPath LWLock 10 Waiting to read or update the fast-path lock information. 11 12 13 Waiting to read or update a process' fast-path lock information. 14 15 16 17 18 19 20 9.6 A brief sa…Wait Events · LWLock LockFileAddtodatadirReadWait EventsReferenceLockFileAddtodatadirRead IO 10 Waiting for a read while adding a line to the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected to perfo…Wait Events · IO LockFileAddtodatadirSyncWait EventsReferenceLockFileAddtodatadirSync IO 10 Waiting for data to reach durable storage while adding a line to the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the worklo…Wait Events · IO LockFileAddtodatadirWriteWait EventsReferenceLockFileAddtodatadirWrite IO 10 Waiting for a write while adding a line to the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected to per…Wait Events · IO LockFileCreateReadWait EventsReferenceLockFileCreateRead IO 10 Waiting to read while creating the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected to perform this read, wri…Wait Events · IO LockFileCreateSyncWait EventsReferenceLockFileCreateSync IO 10 Waiting for data to reach durable storage while creating the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected…Wait Events · IO LockFileCreateWriteWait EventsReferenceLockFileCreateWrite IO 10 Waiting for a write while creating the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected to perform this read…Wait Events · IO LockFileRecheckdatadirReadWait EventsReferenceLockFileRecheckdatadirRead IO 10 Waiting for a read during recheck of the data directory lock file. 11 12 13 14 15 16 17 18 19 20 The wait is normal when the workload is expected to perform …Wait Events · IO Locking and IndexesManual ChaptersPG1813.7. Locking and Indexes Though PostgreSQL provides nonblocking read/write access to table data, nonblocking read/write access is not currently offered for every index access method impleme…Locking and Indexes LockManagerWait EventsReferenceLockManager LWLock 10 Waiting to add or examine locks for backends, or waiting to join or exit a locking group (used by parallel query). 11 12 13 Waiting to read or update information about …Wait Events · LWLock logFunctionsReferencelog Mathematical Functions And Operators 10 base 10 logarithm log ( dp or numeric ) → (same as input) base 10 logarithm log ( b numeric, x numeric ) → numeric logarithm to base b 11 12 13 Ba…Functions · Mathematical Functions And Operators Log File MaintenanceManual ChaptersPG1824.3. Log File Maintenance It is a good idea to save the database server's log output somewhere, rather than just discarding it via /dev/null. The log output is invaluable when diagnosing pr…Log File Maintenance Log-Shipping Standby ServersManual ChaptersPG1826.2. Log-Shipping Standby Servers Continuous archiving can be used to create a high availability (HA) cluster configuration with one or more standby servers ready to take over operations if…Log-Shipping Standby Servers log10FunctionsReferencelog10 Mathematical Functions And Operators 12 base 10 logarithm log10 ( dp or numeric ) → (same as input) base 10 logarithm 13 Base 10 logarithm (same as log) log10 ( numeric ) → numeric Bas…Functions · Mathematical Functions And Operators log_autoanalyze_min_durationConfigurationReferencelog_autoanalyze_min_duration Reporting and Logging 19 Causes analyze action executed by autovacuum to be logged if it ran for at least the specified amount of time. Setting this to zero logs…Configuration · Reporting and Logging log_autovacuum_min_durationConfigurationReferencelog_autovacuum_min_duration Reporting and Logging 10 Causes each action executed by autovacuum to be logged if it ran for at least the specified number of milliseconds. Setting this to zero …Configuration · Reporting and Logging log_btree_build_statsConfigurationReferencelog_btree_build_stats Developer Options 10 If set, logs system resource usage statistics (memory and CPU) on various B-tree operations. This parameter is only available if the BTREE_BUILD_ST…Configuration · Developer Options