This section describes functions that possibly return more than one row. The most widely used functions in this class are series generating functions, as detailed in Table

PostgreSQL is a relational database management system (RDBMS). That means it is

The PostgreSQL type system contains a number of special-purpose entries that are collectively called pseudo-types

An index definition can specify an operator class for each column of an index.

Dictionaries are used to eliminate words that should not be considered in a search (stop words), and to normalize words so

A single index scan can only use query clauses that use the index's columns with operators of its operator class and are joined with AND. For example

The pg_ts_template catalog contains entries defining text search templates. A template is the implementation skeleton for a class of text search

NameDROP GROUP -- remove a database role Synopsis

The catalog pg_statistic stores statistical data about the contents of the database. Entries are created by

NameDROP CAST -- remove a cast Synopsis