CREATE TABLESPACE

NameCREATE TABLESPACE -- define a new tablespace Synopsis CREATE TABLESPACE tablespace_name [ OWNER { new_owner | CURRENT_USER | SESSION_USER } ] LOCATION 'directory' [ WITH ( tablespace_option = value [, ... ] ) ] Description CREATE TABLESPACE registers a new cluster-wide tablespace. The tablespace name must be distinct from the name of any existing tablespace in the database cluster. A tablespace allows superusers to define an alternative location on the file system wher

initdb

Nameinitdb -- create a new PostgreSQL database cluster Synopsis initdb [option...] [--pgdata | -D] directory Description initdb creates a new PostgreSQL database cluster. A database cluster is a collection of databases that are managed by a single server instance. Creating a database cluster consists of creating the directories in which the database data will live, generating the shared catalog tables (tables that belong to the whole cluster rather than to any particular database), and

Internals//Physical Storage: Database File Layout

This section describes the storage format at the level of files and directories. Traditionally, the configuration and data files used by a database cluster are stored together within the cluster's data directory, commonly referred to as PGDATA (after the name of the environment variable that can be used to define it). A common location for PGDATA is /var/lib/pgsql/data. Multiple clusters, managed by different server instances, can exist on the same machine. The PGDATA directory contains several

pg_dumpall

Namepg_dumpall -- extract a PostgreSQL database cluster into a script file Synopsis pg_dumpall [connection-option...] [option...] Description pg_dumpall is a utility for writing out ("dumping") all PostgreSQL databases of a cluster into one script file. The script file contains SQL commands that can be used as input to psql to restore the databases. It does this by calling pg_dump for each database in a cluster. pg_dumpall also dumps global objects that are common to all databases. (pg_

pg_freespacemap

The pg_freespacemap module provides a means for examining the free space map (FSM). It provides a function called pg_freespace, or two overloaded functions, to be precise. The functions show the value recorded in the free space map for a given page, or for all pages in the relation. By default public access is revoked from the functions, just in case there are security issues lurking. F.26.1. Functions pg_freespace(rel regclass IN, blkno bigint IN) returns int2 Returns the amount of

Routine Vacuuming

PostgreSQL databases require periodic maintenance known as vacuuming. For many installations, it is sufficient to let vacuuming be performed by the autovacuum daemon, which is described in Section 24.1.6. You might need to adjust the autovacuuming parameters described there to obtain best results for your situation. Some database administrators will want to supplement or replace the daemon's activities with manually-managed VACUUM commands, which typically are executed according to a schedule b

Internals//Index Access Method: Index Scanning

In an index scan, the index access method is responsible for regurgitating the TIDs of all the tuples it has been told about that match the scan keys. The access method is not involved in actually fetching those tuples from the index's parent table, nor in determining whether they pass the scan's time qualification test or other conditions. A scan key is the internal representation of a WHERE clause of the form index_key operator constant, where the index key is one of the columns of the index

unaccent

unaccent is a text search dictionary that removes accents (diacritic signs) from lexemes. It's a filtering dictionary, which means its output is always passed to the next dictionary (if any), unlike the normal behavior of dictionaries. This allows accent-insensitive processing for full text search. The current implementation of unaccent cannot be used as a normalizing dictionary for the thesaurus dictionary. F.44.1. Configuration An unaccent dictionary accepts the following options: RULES is

fuzzystrmatch

The fuzzystrmatch module provides several functions to determine similarities and distance between strings. Caution: At present, the soundex, metaphone, dmetaphone, and dmetaphone_alt functions do not work well with multibyte encodings (such as UTF-8). F.15.1. Soundex The Soundex system is a method of matching similar-sounding names by converting them to the same code. It was initially used by the United States Census in 1880, 1900, and 1910. Note that Soundex is not very useful for non-Engl

Server Configuration: Connections and Authentication

19.3.1. Connection Settings listen_addresses (string) Specifies the TCP/IP address(es) on which the server is to listen for connections from client applications. The value takes the form of a comma-separated list of host names and/or numeric IP addresses. The special entry * corresponds to all available IP interfaces. The entry 0.0.0.0 allows listening for all IPv4 addresses and :: allows listening for all IPv6 addresses. If the list is empty, the server does not listen on any IP interface