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CREATE TABLESPACE
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CREATE TABLESPACE

CREATE TABLESPACE — define a new tablespace

Synopsis

CREATE TABLESPACEtablespace_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 where the data files containing database objects (such as tables and indexes) can reside.

A user with appropriate privileges can passtablespace_name toCREATE DATABASE,CREATE TABLE,CREATE INDEX orADD CONSTRAINT to have the data files for these objects stored within the specified tablespace.

Warning

A tablespace cannot be used independently of the cluster in which it is defined; seeSection 21.6.

Parameters

tablespace_name: The name of a tablespace to be created. The name cannot begin withpg_, as such names are reserved for system tablespaces.
user_name: The name of the user who will own the tablespace. If omitted, defaults to the user executing the command. Only superusers can create tablespaces, but they can assign ownership of tablespaces to non-superusers.
directory: The directory that will be used for the tablespace. The directory should be empty and must be owned by thePostgres Pro system user. The directory must be specified by an absolute path name.
tablespace_option: A tablespace parameter to be set or reset. Currently, the only available parameters areseq_page_cost andrandom_page_cost. Setting either value for a particular tablespace will override the planner's usual estimate of the cost of reading pages from tables in that tablespace, as established by the configuration parameters of the same name (seeseq_page_cost,random_page_cost). This may be useful if one tablespace is located on a disk which is faster or slower than the remainder of the I/O subsystem.

Notes

Tablespaces are only supported on systems that support symbolic links.

CREATE TABLESPACE cannot be executed inside a transaction block.

Examples

Create a tablespacedbspace at/data/dbs:

CREATE TABLESPACE dbspace LOCATION '/data/dbs';

Create a tablespaceindexspace at/data/indexes owned by usergenevieve:

CREATE TABLESPACE indexspace OWNER genevieve LOCATION '/data/indexes';

Compatibility

CREATE TABLESPACE is aPostgres Pro extension.