PostgreSQL provides facilities to support dynamic tracing of the database server. This allows an external utility to be called at specific points in the code and thereby trace execution. A number of probes or trace points are already inserted into the source code. These probes are intended to be used by database developers and administrators. By default the probes are not compiled into PostgreSQL; the user needs to explicitly tell the configure script to make the probes available. Currently, th

This is a list of acronyms commonly used in the PostgreSQL documentation and in discussions about PostgreSQL. ANSI American National Standards Institute API Application Programming Interface ASCII American Standard Code for Information Interchange BKI Backend Interface CA Certificate Authority CIDR Classless Inter-Domain Routing CPAN Comprehensive Perl Archive Network CRL Certificate Revocation List CSV Comma Separated Values CTE Common Table Expression CVE Common Vulnerab

The functions and function-like expressions described in this section operate on values of type xml. Check Section 8.13 for information about the xml type. The function-like expressions xmlparse and xmlserialize for converting to and from type xml are not repeated here. Use of most of these functions requires the installation to have been built with configure --with-libxml. 9.14.1. Producing XML Content A set of functions and function-like expressions are available for producing XML content fr

This section describes functions for operating on sequence objects, also called sequence generators or just sequences. Sequence objects are special single-row tables created with CREATE SEQUENCE. Sequence objects are commonly used to generate unique identifiers for rows of a table. The sequence functions, listed in Table 9-46, provide simple, multiuser-safe methods for obtaining successive sequence values from sequence objects. Table 9-46. Sequence Functions Function Return Type Description c

Locale support refers to an application respecting cultural preferences regarding alphabets, sorting, number formatting, etc. PostgreSQL uses the standard ISO C and POSIX locale facilities provided by the server operating system. For additional information refer to the documentation of your system. 23.1.1. Overview Locale support is automatically initialized when a database cluster is created using initdb. initdb will initialize the database cluster with the locale setting of its execution env

The BRIN interface has a high level of abstraction, requiring the access method implementer only to implement the semantics of the data type being accessed. The BRIN layer itself takes care of concurrency, logging and searching the index structure. All it takes to get a BRIN access method working is to implement a few user-defined methods, which define the behavior of summary values stored in the index and the way they interact with scan keys. In short, BRIN combines extensibility with generali

Object identifiers (OIDs) are used internally by PostgreSQL as primary keys for various system tables. OIDs are not added to user-created tables, unless WITH OIDS is specified when the table is created, or the default_with_oids configuration variable is enabled. Type oid represents an object identifier. There are also several alias types for oid: regproc, regprocedure, regoper, regoperator, regclass, regtype, regrole, regnamespace, regconfig, and regdictionary. Table 8-24 shows an overview. The

dict_xsyn (Extended Synonym Dictionary) is an example of an add-on dictionary template for full-text search. This dictionary type replaces words with groups of their synonyms, and so makes it possible to search for a word using any of its synonyms. F.12.1. Configuration A dict_xsyn dictionary accepts the following options: matchorig controls whether the original word is accepted by the dictionary. Default is true. matchsynonyms controls whether the synonyms are accepted by the dictionary. D

NameCLUSTER -- cluster a table according to an index Synopsis CLUSTER [VERBOSE] table_name [ USING index_name ] CLUSTER [VERBOSE] Description CLUSTER instructs PostgreSQL to cluster the table specified by table_name based on the index specified by index_name. The index must already have been defined on table_name. When a table is clustered, it is physically reordered based on the index information. Clustering is a one-time operation: when the table is subsequently updated, the changes

Table 50-1 lists the system catalogs. More detailed documentation of each catalog follows below. Most system catalogs are copied from the template database during database creation and are thereafter database-specific. A few catalogs are physically shared across all databases in a cluster; these are noted in the descriptions of the individual catalogs. Table 50-1. System Catalogs Catalog Name Purpose pg_aggregate aggregate functions pg_am index access methods pg_amop access method operators p