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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_ROLE | 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 database administrators to define an alternative location on the file system where the data files containing database objects (such as tables and indexes) can reside. Only superusers and users with the privileges of thepg_create_tablespace role can create tablespaces, but they can assign ownership of tablespaces to non-superusers.

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.
directory: The directory that will be used for the tablespace. The directory must exist (CREATE TABLESPACE will not create it), 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,random_page_cost,effective_io_concurrency andmaintenance_io_concurrency. Setting these values for a particular tablespace will override the planner's usual estimate of the cost of reading pages from tables in that tablespace, and the executor's prefetching behavior, as established by the configuration parameters of the same name (seeseq_page_cost,random_page_cost,effective_io_concurrency,maintenance_io_concurrency). 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

CREATE TABLESPACE cannot be executed inside a transaction block.

Examples

To create a tablespacedbspace at file system location/data/dbs, first create the directory using operating system facilities and set the correct ownership:

mkdir /data/dbschown postgres:postgres /data/dbs

Then issue the tablespace creation command insidePostgres Pro:

CREATE TABLESPACE dbspace LOCATION '/data/dbs';

To create a tablespace owned by a different database user, use a command like this:

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

Compatibility

CREATE TABLESPACE is aPostgres Pro extension.