alter_index(5)

NAME

       ALTER INDEX - change the definition of an index

SYNOPSIS

       ALTER INDEX name RENAME TO new_name
       ALTER INDEX name SET TABLESPACE tablespace_name
       ALTER INDEX name SET ( storage_parameter = value [, ... ] )
       ALTER INDEX 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  [cre-
              ate_tablespace(5)].

       SET ( storage_parameter = value [, ... ] )
              This form changes  one  or  more  index-method-specific  storage
              parameters for the index. See CREATE INDEX [create_index(5)] for
              details on the available parameters. Note that  the  index  con-
              tents  will not be modified immediately by this command; depend-
              ing on the parameter you may need  to  rebuild  the  index  with
              REINDEX [reindex(5)] 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  may  be
              needed to update the index entirely.

PARAMETERS

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

       new_name
              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(5)].
       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  sup-
       ports it):

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

COMPATIBILITY

       ALTER INDEX is a PostgreSQL extension.

SEE ALSO

       CREATE INDEX [create_index(5)], REINDEX [reindex(l)]

SQL - Language Statements         2008-06-08                     ALTER INDEX()