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aws_lambdaExtensionsExtensionsAmazon RDS for PostgreSQL extension for invoking AWS Lambda functions from SQL. aws lambda serverless aws_lambda UtilitiesUtilities · Extensions aws_mlExtensionsExtensionsAmazon Aurora PostgreSQL extension for invoking Amazon Comprehend, SageMaker AI, and Bedrock services from SQL. ai aurora aws bedrock machine-learning aws_ml AI and vectorsAI and vectors · Extensions aws_s3ExtensionsExtensionsaws_s3 postgres extension to import/export data from/to s3 aws_s3 Foreign data wrappersForeign data wrappers · Extensions azure_aiExtensionsExtensionsAzure Database for PostgreSQL extension for in-database calls to Azure AI, Azure OpenAI, Cognitive Services, and Azure Machine Learning. ai azure ml azure_ai AI and vectorsAI and vectors · Extensions azure_storageExtensionsExtensionsAzure Database for PostgreSQL extension for importing from and exporting to Azure Storage blobs from SQL. azure blob-storage etl azure_storage Replication and streamsReplication and streams · Extensions B-TreeManual ChaptersPG1811.2.1. B-Tree B-trees can handle equality and range queries on data that can be sorted into some ordering. In particular, the PostgreSQL query planner will consider using a B-tree index whe…B-Tree B-Tree FunctionsManual ChaptersPG18F.23.3. B-Tree Functions bt_metap(relname text) returns record bt_metap returns information about a B-tree index's metapage. For example: test=# SELECT * FROM bt_metap('pg_cast_oid_index'); …B-Tree Functions B-Tree IndexesManual ChaptersPG1865.1. B-Tree IndexesB-Tree Indexes B-Tree StructureManual ChaptersPG1865.1.4.1. B-Tree Structure PostgreSQL B-Tree indexes are multi-level tree structures, where each level of the tree can be used as a doubly-linked list of pages. A single metapage is stored i…B-Tree Structure B-Tree Support FunctionsManual ChaptersPG1865.1.3. B-Tree Support Functions As shown in Table 36.9, btree defines one required and five optional support functions. The six user-defined methods are: order For each combination of data …B-Tree Support Functions b64encExtensionsExtensionsRust/C extension that defines a b64enc base type with URL-safe Base64 input and output functions. base64 data-type pg_b64enc_rust Data typesData types · Extensions babelfishpg_commonExtensionsExtensionsSQL Server Transact SQL Datatype Support fork mssql babelfish CompatibilityCompatibility · Extensions babelfishpg_moneyExtensionsExtensionsSQL Server Money Data Type fork mssql babelfish CompatibilityCompatibility · Extensions babelfishpg_tdsExtensionsExtensionsSQL Server TDS protocol extension fork mssql babelfish CompatibilityCompatibility · Extensions babelfishpg_tsqlExtensionsExtensionsSQL Server Transact SQL compatibility fork mssql babelfish CompatibilityCompatibility · Extensions babelfishpg_unitExtensionsExtensionsC test runner for invoking all or selected Babelfish unit tests from SQL. database postgresql sqlserver babelfishpg_unit FeaturesFeatures · Extensions backend_flush_afterConfigurationReferencebackend_flush_after Resource Usage 10 Whenever more than backend_flush_after bytes have been written by a single backend, attempt to force the OS to issue these writes to the underlying stor…Configuration · Resource Usage BackendRandomLockWait EventsReferenceBackendRandomLock LWLock 10 Waiting to generate a random number. 11Wait Events · LWLock BackendTerminationWait EventsReferenceBackendTermination IPC 14 Waiting for the termination of another backend. 15 16 17 18 19 20 Brief rendezvous is normal when every participant continues to advance. Investigate when the same …Wait Events · IPC Background Worker ProcessesManual ChaptersPG18Chapter 46. Background Worker Processes PostgreSQL can be extended to run user-supplied code in separate processes. Such processes are started, stopped and monitored by postgres, which permi…Background Worker Processes Background WriterManual ChaptersPG1819.4.4. Background Writer There is a separate server process called the background writer, whose function is to issue writes of “dirty” (new or modified) shared buffers. When the number of c…Background Writer BackgroundWorkerWait EventsReferenceBackgroundWorker LWLock 10 Waiting to read or update background worker state. 11 12 13 14 15 16 17 18 19 20 9.6 A brief sample is normal around short internal critical sections. Investigate …Wait Events · LWLock Backing Up the Data DirectoryManual ChaptersPG1825.3.4.1. Backing Up the Data Directory Some file system backup tools emit warnings or errors if the files they are trying to copy change while the copy proceeds. When taking a base backup o…Backing Up the Data Directory backslash_quoteConfigurationReferencebackslash_quote Version and Platform Compatibility 10 This controls whether a quote mark can be represented by \' in a string literal. The preferred, SQL-standard way to represent a quote ma…Configuration · Version and Platform Compatibility backtrace_functionsConfigurationReferencebacktrace_functions Developer Options 13 This parameter contains a comma-separated list of C function names. If an error is raised and the name of the internal C function where the error hap…Configuration · Developer Options Backup and RestoreManual ChaptersPG18Chapter 25. Backup and Restore As with everything that contains valuable data, PostgreSQL databases should be backed up regularly. While the procedure is essentially simple, it is important …Backup and Restore Backup Control FunctionsManual ChaptersPG189.28.3. Backup Control Functions The functions shown in Table 9.97 assist in making on-line backups. These functions cannot be executed during recovery (except pg_backup_start, pg_backup_sto…Backup Control Functions Backup Manifest File ObjectManual ChaptersPG1870.2. Backup Manifest File Object The object which describes a single file contains either a Path key or an Encoded-Path key. Normally, the Path key will be present. The associated string va…Backup Manifest File Object Backup Manifest FormatManual ChaptersPG18Chapter 70. Backup Manifest Format The backup manifest generated by pg_basebackup is primarily intended to permit the backup to be verified using pg_verifybackup. However, it is also possibl…Backup Manifest Format Backup Manifest Top-level ObjectManual ChaptersPG1870.1. Backup Manifest Top-level Object The backup manifest JSON document contains the following keys. PostgreSQL-Backup-Manifest-Version The associated value is an integer. Beginning in Post…Backup Manifest Top-level Object Backup Manifest WAL Range ObjectManual ChaptersPG1870.3. Backup Manifest WAL Range Object The object which describes a WAL range always has three keys: Timeline The timeline for this range of WAL records, as an integer. Start-LSN The LSN at …Backup Manifest WAL Range Object BackupWaitWalArchiveWait EventsReferenceBackupWaitWalArchive IPC 13 Waiting for WAL files required for a backup to be successfully archived. 14 15 16 17 18 19 20 Brief rendezvous is normal when every participant continues to advan…Wait Events · IPC badappleExtensionsExtensionsPlay "Bad Apple!!" in the psql client. badapple postgresql postgresql-extension badapple FeaturesFeatures · Extensions bankbsbExtensionsExtensionsPostgres Extension for Australian BSB numbers data type. bankbsb Data typesData types · Extensions Base Backup Progress ReportingManual ChaptersPG1827.4.6. Base Backup Progress Reporting Whenever an application like pg_basebackup is taking a base backup, the pg_stat_progress_basebackup view will contain a row for each WAL sender process…Base Backup Progress Reporting Base TypesManual ChaptersPG1836.2.1. Base Types Base types are those, like integer, that are implemented below the level of the SQL language (typically in a low-level language such as C). They generally correspond to wh…Base Types Base TypesManual ChaptersPG18Base Types The fourth form of CREATE TYPE creates a new base type (scalar type). To create a new base type, you must be a superuser. (This restriction is made because an erroneous type defin…Base Types Base Types in C-Language FunctionsManual ChaptersPG1836.10.2. Base Types in C-Language Functions To know how to write C-language functions, you need to know how PostgreSQL internally represents base data types and how they can be passed to and…Base Types in C-Language Functions base32_4bExtensionsExtensionsBase32 data type stored in four bytes with comparison operators. base32 data-type base32_4b Data typesData types · Extensions base36ExtensionsExtensionsInteger Base36 types pg_base36 Functions and aggregatesFunctions and aggregates · Extensions