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launchql-extension-jobsExtensionsExtensionsFeatures · ExtensionsLegacy LaunchQL asynchronous job queue with an external Node.js worker queue jobs launchql-extension-jobs Features launchql-extension-utilsExtensionsExtensionsUtilities · ExtensionsPostgreSQL utilities launchql-extension-utils Utilities launchql-extension-verifyExtensionsExtensionsFeatures · ExtensionsPostgreSQL verification utilities launchql-extension-verify Features launchql-inflectionExtensionsExtensionsFunctions and aggregates · Extensionsinflection is a port of the functionality from Ruby on Rails' Active Support Inflection classes into PostgreSQL launchql-inflection Functions and aggregates launchql-jwt-claimsExtensionsExtensionsSecurity · Extensionsextension dependency-closure launchql-jwt-claims source-only sql launchql-jwt-claims Security launchql-stampsExtensionsExtensionsFunctions and aggregates · Extensions🛠. basic pg utils launchql-stamps Functions and aggregates launchql-totpExtensionsExtensionsSecurity · Extensions🛠. basic pg utils launchql-totp Security lcaFunctionsPG18ltree — hierarchical tree-like data type › Operators and Functions( ltree [, ltree [, ... ]] ) → ltree Computes longest common ancestor of paths (up to 8 arguments are supported). lca('1.2.3', '1.2.3.4.5.6') → 1.2 LDAP AuthenticationManual ChaptersPG18This authentication method operates similarly to password except that it uses LDAP as the password verification method. LDAP is used only to validate the user name/password pairs. Therefore … LDAP Lookup of Connection ParametersManual ChaptersPG18If libpq has been compiled with LDAP support (option --with-ldap for configure) it is possible to retrieve connection options like host or dbname via LDAP from a central server. The advantag… ldap_fdwExtensionsExtensionsForeign data wrappers · ExtensionsForeign data wrapper for querying LDAP servers external-data fdw ldap sql-med ldap_fdw Foreign data wrappers LEASTSQL CommandsPG18Conditional Expressions › GREATEST and LEAST9.18.4. GREATEST and LEAST # GREATEST(value [, ...]) LEAST(value [, ...]) The GREATEST and LEAST functions select the largest or smallest value from a list of any number of expressions. The … Legal NoticeManual ChaptersPG18PostgreSQL Database Management System (also known as Postgres, formerly known as Postgres95) Portions Copyright © 1996-2026, PostgreSQL Global Development Group Portions Copyright © 1994, Th… letterExtensionsExtensionsSecurity · Extensionsrole-based access control for PostgreSQL letter Security level_pivotExtensionsExtensionsForeign data wrappers · ExtensionsLevelDB FDW with support for pivoting and key templating level_pivot Foreign data wrappers LevenshteinManual ChaptersPG18fuzzystrmatch — determine string similarities and distanceThis function calculates the Levenshtein distance between two strings: levenshtein(source text, target text, ins_cost int, del_cost int, sub_cost int) returns int levenshtein(source text, ta… Lexical StructureManual ChaptersPG18SQL input consists of a sequence of commands. A command is composed of a sequence of tokens, terminated by a semicolon (“;”). The end of the input stream also terminates a command. Which tok… lextestExtensionsExtensionsFeatures · ExtensionsTiny module for PostgreSQL lexer benchmarking benchmarking lexer lextest Features li3dsExtensionsExtensionsGeospatial · ExtensionsPostgreSQL extension for managing 3D sensor data li3ds Geospatial libc CollationsManual ChaptersPG18Collation SupportFor example, the operating system might provide a locale named de_DE.utf8. initdb would then create a collation named de_DE.utf8 for encoding UTF8 that has both LC_COLLATE and LC_CTYPE set t… libc CollationsManual ChaptersPG18Collation SupportNew libc collations can be created like this: CREATE COLLATION german (provider = libc, locale = 'de_DE'); The exact values that are acceptable for the locale clause in this command depend o… LibpqManual ChaptersPG18Release 18Add function PQfullProtocolVersion() to report the full, including minor, protocol version number (Jacob Champion, Jelte Fennema-Nio) § Add libpq connection parameters and environment variab… libpq — C LibraryManual ChaptersPG18libpq is the C application programmer's interface to PostgreSQL. libpq is a set of library functions that allow client programs to pass queries to the PostgreSQL backend server and to receiv… Library FunctionsManual ChaptersPG18The libecpg library primarily contains “hidden” functions that are used to implement the functionality expressed by the embedded SQL commands. But there are some functions that can usefully … libuuidExtensionsExtensionsFunctions and aggregates · ExtensionsGenerate UUIDs through the system libuuid library function uuid pglibuuid Functions and aggregates libversionExtensionsExtensionsData types · ExtensionsVersion string comparison functions and versiontext type using libversion comparison datatype version postgresql-libversion Data types libx509pqExtensionsExtensionsSecurity · ExtensionsX.509 certificate parsing library for PostgreSQL certificate openssl security x509 libx509pq Security LIKEManual ChaptersPG18Pattern Matchingstring LIKE pattern [ESCAPE escape-character] string NOT LIKE pattern [ESCAPE escape-character] The LIKE expression returns true if the string matches the supplied pattern. (As expected, the… LIKESQL CommandsPG18CREATE TABLE › Compatibility › LIKE ClauseClause While a LIKE clause exists in the SQL standard, many of the options that PostgreSQL accepts for it are not in the standard, and some of the standard's options are not implemented by P… LIKE ClauseManual ChaptersPG18CREATE TABLEWhile a LIKE clause exists in the SQL standard, many of the options that PostgreSQL accepts for it are not in the standard, and some of the standard's options are not implemented by PostgreS… LIMITSQL CommandsPG18LIMIT and OFFSETand OFFSET # LIMIT and OFFSET allow you to retrieve just a portion of the rows that are generated by the rest of the query: SELECT select_list FROM table_expression [ ORDER BY ... ] [ LIMIT … LIMIT and OFFSETManual ChaptersPG18allow you to retrieve just a portion of the rows that are generated by the rest of the query: SELECT select_list FROM table_expression [ ORDER BY ... ] [ LIMIT { count | ALL } ] [ OFFSET sta… LIMIT and OFFSETManual ChaptersPG18SELECTThe clauses LIMIT and OFFSET are PostgreSQL-specific syntax, also used by MySQL. The SQL:2008 standard has introduced the clauses OFFSET ... FETCH {FIRST|NEXT} ... for the same functionality… LIMIT ClauseManual ChaptersPG18SELECTThe LIMIT clause consists of two independent sub-clauses: LIMIT { count | ALL } OFFSET start The parameter count specifies the maximum number of rows to return, while start specifies the num… LimitationsManual ChaptersPG18pg_combinebackuppg_combinebackup does not recompute page checksums when writing the output directory. Therefore, if any of the backups used for reconstruction were taken with checksums disabled, but the fin… LimitationsManual ChaptersPG18bloom — bloom filter index access methodOnly operator classes for int4 and text are included with the module. Only the = operator is supported for search. But it is possible to add support for arrays with union and intersection op… LimitationsManual ChaptersPG18citext — a case-insensitive character string typecitext's case-folding behavior depends on the LC_CTYPE setting of your database. How it compares values is therefore determined when the database is created. It is not truly case-insensitive… LimitationsManual ChaptersPG18Table PartitioningThe following limitations apply to partitioned tables: To create a unique or primary key constraint on a partitioned table, the partition keys must not include any expressions or function ca… LimitationsManual ChaptersPG18GIN IndexesGIN assumes that indexable operators are strict. This means that extractValue will not be called at all on a null item value (instead, a placeholder index entry is created automatically), an… LimitationsManual ChaptersPG18lo — manage large objectsDropping a table will still orphan any objects it contains, as the trigger is not executed. You can avoid this by preceding the DROP TABLE with DELETE FROM table. TRUNCATE has the same hazar…