Search PostgreSQL documentation

Namespace Available to GROUP BY and ORDER BYManual ChaptersPG18SELECTIn the SQL-92 standard, an ORDER BY clause can only use output column names or numbers, while a GROUP BY clause can only use expressions based on input column names. PostgreSQL extends each … nanomsgtopdbExtensionsExtensionsReplication and streams · ExtensionsReceive nanomsg messages into a PipelineDB stream. background-worker nanomsg pipelinedb nanomsgtopdb Replication and streams narugnExtensionsExtensionsAnalytics · ExtensionsA lightweight distributed computer narugn Analytics Native Language SupportManual ChaptersPG18 natord_pgExtensionsExtensionsFunctions and aggregates · ExtensionsNatural-order comparison operators and btree operator class for PostgreSQL text values. operator ordering pgrx natord_pg Functions and aggregates NEGATORManual ChaptersPG18Operator Optimization InformationThe NEGATOR clause, if provided, names an operator that is the negator of the operator being defined. We say that operator A is the negator of operator B if both return Boolean results and (… neo4j-fdwExtensionsExtensionsForeign data wrappers · ExtensionsMulticorn-based foreign data wrapper and Cypher functions for Neo4j. fdw multicorn neo4j plpython neo4j-fdw Foreign data wrappers neo4j_fdwExtensionsExtensionsForeign data wrappers · ExtensionsC foreign data wrapper for Neo4j Cypher query results. fdw neo4j neo4j_fdw Foreign data wrappers neonExtensionsExtensionsMonitoring · Extensionsspecific statistics and Local File Cache metrics for Neon Postgres computes. cloud metrics preload storage neon Monitoring neon_utilsExtensionsExtensionsMonitoring · ExtensionsMonitor Neon Autoscaling compute allocation with num_cpus(). autoscaling neon neon_utils Monitoring Network Address Functions and OperatorsManual ChaptersPG18The IP network address types, cidr and inet, support the usual comparison operators shown in Table 9.1 as well as the specialized operators and functions shown in Table 9.39 and Table 9.40. … Network Address TypesManual ChaptersPG18PostgreSQL offers data types to store IPv4, IPv6, and MAC addresses, as shown in Table 8.21. It is better to use these types instead of plain text types to store network addresses, because t… neurondbExtensionsExtensionsAI and vectors · ExtensionsAI database extension for vector search, ML inference, hybrid search, and RAG in PostgreSQL. background-worker ml non-free rag vector neurondb AI and vectors newsfeedsExtensionsExtensionsFeatures · ExtensionsPostgreSQL extension for gathering news pg_newsfeeds Features newtricksExtensionsExtensionsFeatures · ExtensionsExamples of postgres extensions using rust pgrx rust newtricks Features nextgres_idcpExtensionsExtensionsAdministration · ExtensionsNEXTGRES in-database connection pool extension for PostgreSQL. background-worker non-free pooler nextgres_idcp Administration nextidExtensionsExtensionsFunctions and aggregates · ExtensionsGenerate Instagram-style sharded integer IDs. id-generator pg_nextid Functions and aggregates nfiestaExtensionsExtensionsFunctions and aggregates · ExtensionsPostgreSQL extension implementing nFIESTA forest inventory estimation functionality. estimation forestry postgis nfiesta Functions and aggregates nfiesta_gisdataExtensionsExtensionsGeospatial · Extensionsnfi gisdata database auxiliary variable greg estimator postgis nfiesta_gisdata Geospatial nfiesta_sdesignExtensionsExtensionsFunctions and aggregates · ExtensionsPostgreSQL extension for manipulating sampling design data. postgis sampling-design nfiesta_sdesign Functions and aggregates nfiesta_target_dataExtensionsExtensionsGeospatial · ExtensionsPostgreSQL extension for manipulation of target data - aggregation of local density contributions at the plot level. nfiesta_target_data Geospatial NFSManual ChaptersPG18Creating a Database ClusterIt is possible to use an NFS file system for storing the PostgreSQL data directory. PostgreSQL does nothing special for NFS file systems, meaning it assumes NFS behaves exactly like locally-… nlevelFunctionsPG18ltree — hierarchical tree-like data type › Operators and Functions( ltree ) → integer Returns number of labels in path. nlevel('Top.Child1.Child2') → 3 No XML(SEQUENCE) TypeManual ChaptersPG18XML Limits and Conformance to SQL/XMLThe PostgreSQL xml data type can only hold a value in DOCUMENT or CONTENT form. An XQuery/XPath expression context item must be a single XML node or atomic value, but XPath 1.0 further restr… noddlExtensionsExtensionsSecurity · ExtensionsCluster-wide DDL blocker with role and database exceptions. ddl guard security hook noddl Security nominatim_fdwExtensionsExtensionsForeign data wrappers · ExtensionsNominatim Foreign Data Wrapper for PostgreSQL nominatim_fdw Foreign data wrappers Non-Deferred Uniqueness ConstraintsManual ChaptersPG18CREATE TABLEWhen a UNIQUE or PRIMARY KEY constraint is not deferrable, PostgreSQL checks for uniqueness immediately whenever a row is inserted or modified. The SQL standard says that uniqueness should b… Non-Durable SettingsManual ChaptersPG18Durability is a database feature that guarantees the recording of committed transactions even if the server crashes or loses power. However, durability adds significant database overhead, so… non_truncateExtensionsExtensionsAdministration · ExtensionsDisables TRUNCATE by raising an error from a ProcessUtility hook ddl guardrail processutility truncate non_truncate Administration Nondeterministic CollationsManual ChaptersPG18Collation SupportA collation is either deterministic or nondeterministic. A deterministic collation uses deterministic comparisons, which means that it considers strings to be equal only if they consist of t… nonomsExtensionsExtensionsFeatures · ExtensionsNormalised nomenclatural system for managing biological names and taxonomic understandings in PostgreSQL. biology nomenclature nonoms Features Nonstandard ClausesManual ChaptersPG18SELECTDISTINCT ON ( ... ) is an extension of the SQL standard. ROWS FROM( ... ) is an extension of the SQL standard. The MATERIALIZED and NOT MATERIALIZED options of WITH are extensions of the SQL… norasearchExtensionsExtensionsFull-text search · Extensionsis a high-performance search engine for PostgreSQL. norasearch Full-text search normExtensionsExtensionsFeatures · ExtensionsNo-ORM helper extension that generates simple CRUD functions. crud orm norm Features normal_randFunctionsPG18tablefunc — functions that return tables (crosstab and others) › Functions Provided( numvals integer, mean float8, stddev float8 ) → setof float8 Produces a set of normally distributed random values. normal_randManual ChaptersPG18tablefunc — functions that return tables (crosstab and others)(int numvals, float8 mean, float8 stddev) returns setof float8 normal_rand produces a set of normally distributed random values (Gaussian distribution). numvals is the number of values to be… nosetExtensionsExtensionsSecurity · ExtensionsModule for blocking SET variables for non-super users. pg_noset Security nostr_filterExtensionsExtensionsFeatures · ExtensionsNostr event types, insertion helpers, and JSON filter evaluation inside PostgreSQL. nostr event filter json nostr_filter Features NOT INSQL CommandsPG18Row and Array Comparisons › NOT IN# expression NOT IN (value [, ...]) The right-hand side is a parenthesized list of expressions. The result is “true” if the left-hand expression's result is unequal to all of the right-hand … NOT INManual ChaptersPG18Row and Array Comparisonsexpression NOT IN (value [, ...]) The right-hand side is a parenthesized list of expressions. The result is “true” if the left-hand expression's result is unequal to all of the right-hand ex…