ALTER INDEX(7)		PostgreSQL 9.2.24 Documentation		ALTER INDEX(7)



NAME
       ALTER_INDEX - change the definition of an index

SYNOPSIS
       ALTER INDEX [ IF EXISTS ] name RENAME TO new_name
       ALTER INDEX [ IF EXISTS ] name SET TABLESPACE tablespace_name
       ALTER INDEX [ IF EXISTS ] name SET ( storage_parameter = value [, ... ] )
       ALTER INDEX [ IF EXISTS ] name RESET ( storage_parameter [, ... ] )

DESCRIPTION
       ALTER INDEX changes the definition of an existing index. There are
       several subforms:

       RENAME
	   The RENAME form changes the name of the index. There is no effect
	   on the stored data.

       SET TABLESPACE
	   This form changes the index's tablespace to the specified
	   tablespace and moves the data file(s) associated with the index to
	   the new tablespace. See also CREATE TABLESPACE
	   (CREATE_TABLESPACE(7)).

       SET ( storage_parameter = value [, ... ] )
	   This form changes one or more index-method-specific storage
	   parameters for the index. See CREATE INDEX (CREATE_INDEX(7)) for
	   details on the available parameters. Note that the index contents
	   will not be modified immediately by this command; depending on the
	   parameter you might need to rebuild the index with REINDEX(7) to
	   get the desired effects.

       RESET ( storage_parameter [, ... ] )
	   This form resets one or more index-method-specific storage
	   parameters to their defaults. As with SET, a REINDEX might be
	   needed to update the index entirely.

PARAMETERS
       IF EXISTS
	   Do not throw an error if the index does not exist. A notice is
	   issued in this case.

       name
	   The name (possibly schema-qualified) of an existing index to alter.

       new_name
	   The new name for the index.

       tablespace_name
	   The tablespace to which the index will be moved.

       storage_parameter
	   The name of an index-method-specific storage parameter.

       value
	   The new value for an index-method-specific storage parameter. This
	   might be a number or a word depending on the parameter.

NOTES
       These operations are also possible using ALTER TABLE (ALTER_TABLE(7)).
       ALTER INDEX is in fact just an alias for the forms of ALTER TABLE that
       apply to indexes.

       There was formerly an ALTER INDEX OWNER variant, but this is now
       ignored (with a warning). An index cannot have an owner different from
       its table's owner. Changing the table's owner automatically changes the
       index as well.

       Changing any part of a system catalog index is not permitted.

EXAMPLES
       To rename an existing index:

	   ALTER INDEX distributors RENAME TO suppliers;

       To move an index to a different tablespace:

	   ALTER INDEX distributors SET TABLESPACE fasttablespace;

       To change an index's fill factor (assuming that the index method
       supports it):

	   ALTER INDEX distributors SET (fillfactor = 75);
	   REINDEX INDEX distributors;

COMPATIBILITY
       ALTER INDEX is a PostgreSQL extension.

SEE ALSO
       CREATE INDEX (CREATE_INDEX(7)), REINDEX(7)



PostgreSQL 9.2.24		  2017-11-06			ALTER INDEX(7)