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OpenSSL Support FunctionsManual ChaptersPG18pgcrypto — cryptographic functionsfips_mode() returns boolean Returns true if OpenSSL is running with FIPS mode enabled, otherwise false. opentdeExtensionsExtensionsSecurity · ExtensionsOpen Transparent Data Encryption for PostgreSQL. opentde Security Operator Class InterfaceManual ChaptersPG18bloom — bloom filter index access methodAn operator class for bloom indexes requires only a hash function for the indexed data type and an equality operator for searching. This example shows the operator class definition for the t… Operator Class ParametersManual ChaptersPG18BRIN IndexesSome of the built-in operator classes allow specifying parameters affecting behavior of the operator class. Each operator class has its own set of allowed parameters. Only the bloom and minm… Operator Classes and Operator FamiliesManual ChaptersPG18An index definition can specify an operator class for each column of an index. CREATE INDEX name ON table (column opclass [ ( opclass_options ) ] [sort options] [, ...]); The operator class … Operator Classes and Operator FamiliesManual ChaptersPG18Interfacing Extensions to IndexesSo far we have implicitly assumed that an operator class deals with only one data type. While there certainly can be only one data type in a particular index column, it is often useful to in… Operator InvocationsManual ChaptersPG18Value ExpressionsThere are two possible syntaxes for an operator invocation: expression operator expression (binary infix operator) operator expression (unary prefix operator) where the operator token follow… Operator Optimization InformationManual ChaptersPG18A PostgreSQL operator definition can include several optional clauses that tell the system useful things about how the operator behaves. These clauses should be provided whenever appropriate… Operator PrecedenceManual ChaptersPG18Lexical StructureTable 4.2 shows the precedence and associativity of the operators in PostgreSQL. Most operators have the same precedence and are left-associative. The precedence and associativity of the ope… OperatorsManual ChaptersPG18Lexical StructureAn operator name is a sequence of up to NAMEDATALEN-1 (63 by default) characters from the following list: + - * / < > = ~ ! @ # % ^ & | ` ? There are a few restrictions on operator names, ho… OperatorsManual ChaptersPG18The specific operator that is referenced by an operator expression is determined using the following procedure. Note that this procedure is indirectly affected by the precedence of the opera… Operators and FunctionsManual ChaptersPG18ltree — hierarchical tree-like data typeType ltree has the usual comparison operators =, <>, <, >, <=, >=. Comparison sorts in the order of a tree traversal, with the children of a node sorted by label text. In addition, the speci… opm_coreExtensionsExtensionsMonitoring · ExtensionsCentral module of the OPM suite opm_core Monitoring optimExtensionsExtensionsData types · ExtensionsExperimental pgrx extension defining optimization-direction and hyperparameter trial types. pgrx optim Data types OptimizationManual ChaptersPG18What Is JIT compilation?LLVM has support for optimizing generated code. Some of the optimizations are cheap enough to be performed whenever JIT is used, while others are only beneficial for longer-running queries. … optimized_row_formatExtensionsExtensionsAnalytics · ExtensionsExperimental table access method for compact, cache-friendly row storage. table-am storage row-format compression optimized_row_format Analytics OptimizerManual ChaptersPG18Release 18Automatically remove some unnecessary table self-joins (Andrey Lepikhov, Alexander Kuzmenkov, Alexander Korotkov, Alena Rybakina) § This optimization can be disabled using server variable en… Optimizing PL/pgSQL FunctionsManual ChaptersPG18Porting from Oracle PL/SQLPostgreSQL gives you two function creation modifiers to optimize execution: “volatility” (whether the function always returns the same result when given the same arguments) and “strictness” … Optional heapallindexed VerificationManual ChaptersPG18amcheck — tools to verify table and index consistencyWhen the heapallindexed argument to B-Tree verification functions is true, an additional phase of verification is performed against the table associated with the target index relation. This … OptionsManual ChaptersPG18clusterdbclusterdb accepts the following command-line arguments: -a--all Cluster all databases. [-d] dbname[--dbname=]dbname Specifies the name of the database to be clustered, when -a/--all is not u… OptionsManual ChaptersPG18createdbcreatedb accepts the following command-line arguments: dbname Specifies the name of the database to be created. The name must be unique among all PostgreSQL databases in this cluster. The de… OptionsManual ChaptersPG18createusercreateuser accepts the following command-line arguments: username Specifies the name of the PostgreSQL user to be created. This name must be different from all existing roles in this Postgre… OptionsManual ChaptersPG18dropdbdropdb accepts the following command-line arguments: dbname Specifies the name of the database to be removed. -e--echo Echo the commands that dropdb generates and sends to the server. -f--fo… OptionsManual ChaptersPG18dropuserdropuser accepts the following command-line arguments: username Specifies the name of the PostgreSQL user to be removed. You will be prompted for a name if none is specified on the command l… OptionsManual ChaptersPG18ecpgecpg accepts the following command-line arguments: -c Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE. -C mode Set a compatibility mode. mode can… OptionsManual ChaptersPG18initdbA authmethod--auth=authmethod # This option specifies the default authentication method for local users used in pg_hba.conf (host and local lines). See Section 20.1 for an overview of valid … OptionsManual ChaptersPG18pg_ctlc--core-files Attempt to allow server crashes to produce core files, on platforms where this is possible, by lifting any soft resource limit placed on core files. This is useful in debugging… OptionsManual ChaptersPG18pg_dumpallThe following command-line options control the content and format of the output. -a--data-only Dump only the data, not the schema (data definitions) or statistics. -c--clean Emit SQL command… OptionsManual ChaptersPG18pg_isreadyd dbname--dbname=dbname Specifies the name of the database to connect to. The dbname can be a connection string. If so, connection string parameters will override any conflicting command lin… OptionsManual ChaptersPG18pg_amcheckThe following command-line options control what is checked: -a--all Check all databases, except for any excluded via --exclude-database. -d pattern--database=pattern Check databases matching… OptionsManual ChaptersPG18pg_basebackupThe following command-line options control the location and format of the output: -D directory--pgdata=directory Sets the target directory to write the output to. pg_basebackup will create t… OptionsManual ChaptersPG18pg_checksumsThe following command-line options are available: -D directory--pgdata=directory Specifies the directory where the database cluster is stored. -c--check Checks checksums. This is the default… OptionsManual ChaptersPG18pg_combinebackupd--debug Print lots of debug logging output on stderr. -k--link Use hard links instead of copying files to the synthetic backup. Reconstruction of the synthetic backup might be faster (no fi… OptionsManual ChaptersPG18pg_configTo use pg_config, supply one or more of the following options: --bindir Print the location of user executables. Use this, for example, to find the psql program. This is normally also the loc… OptionsManual ChaptersPG18pg_createsubscriberpg_createsubscriber accepts the following command-line arguments: -a--all Create one subscription per database on the target server. Exceptions are template databases and databases that don'… OptionsManual ChaptersPG18pg_dumpThe following command-line options control the content and format of the output. dbname Specifies the name of the database to be dumped. If this is not specified, the environment variable PG… OptionsManual ChaptersPG18pg_receivewalD directory--directory=directory Directory to write the output to. This parameter is required. -E lsn--endpos=lsn Automatically stop replication and exit with normal exit status 0 when recei… OptionsManual ChaptersPG18pg_recvlogicalAt least one of the following options must be specified to select an action: --create-slot Create a new logical replication slot with the name specified by --slot, using the output plugin sp… OptionsManual ChaptersPG18pg_resetwaldatadir-D datadir--pgdata=datadir Specifies the location of the database directory. For safety reasons, you must specify the data directory on the command line. pg_resetwal does not use the … OptionsManual ChaptersPG18pg_restorepg_restore accepts the following command line arguments. filename Specifies the location of the archive file (or directory, for a directory-format archive) to be restored. If not specified, …