NAME

       ALTER_VIEW - change the definition of a view

SYNOPSIS

       ALTER VIEW [ IF EXISTS ] name ALTER [ COLUMN ] column_name SET DEFAULT expression
       ALTER VIEW [ IF EXISTS ] name ALTER [ COLUMN ] column_name DROP DEFAULT
       ALTER VIEW [ IF EXISTS ] name OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
       ALTER VIEW [ IF EXISTS ] name RENAME [ COLUMN ] column_name TO new_column_name
       ALTER VIEW [ IF EXISTS ] name RENAME TO new_name
       ALTER VIEW [ IF EXISTS ] name SET SCHEMA new_schema
       ALTER VIEW [ IF EXISTS ] name SET ( view_option_name [= view_option_value] [, ... ] )
       ALTER VIEW [ IF EXISTS ] name RESET ( view_option_name [, ... ] )

DESCRIPTION

       ALTER VIEW changes various auxiliary properties of a view. (If you want to modify the
       view's defining query, use CREATE OR REPLACE VIEW.)

       You must own the view to use ALTER VIEW. To change a view's schema, you must also have
       CREATE privilege on the new schema. To alter the owner, you must also be a direct or
       indirect member of the new owning role, and that role must have CREATE privilege on the
       view's schema. (These restrictions enforce that altering the owner doesn't do anything you
       couldn't do by dropping and recreating the view. However, a superuser can alter ownership
       of any view anyway.)

PARAMETERS

       name
           The name (optionally schema-qualified) of an existing view.

       column_name
           Name of an existing column.

       new_column_name
           New name for an existing column.

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

       SET/DROP DEFAULT
           These forms set or remove the default value for a column. A view column's default
           value is substituted into any INSERT or UPDATE command whose target is the view,
           before applying any rules or triggers for the view. The view's default will therefore
           take precedence over any default values from underlying relations.

       new_owner
           The user name of the new owner of the view.

       new_name
           The new name for the view.

       new_schema
           The new schema for the view.

       SET ( view_option_name [= view_option_value] [, ... ] )
       RESET ( view_option_name [, ... ] )
           Sets or resets a view option. Currently supported options are:

           check_option (enum)
               Changes the check option of the view. The value must be local or cascaded.

           security_barrier (boolean)
               Changes the security-barrier property of the view. The value must be Boolean
               value, such as true or false.

NOTES

       For historical reasons, ALTER TABLE can be used with views too; but the only variants of
       ALTER TABLE that are allowed with views are equivalent to the ones shown above.

EXAMPLES

       To rename the view foo to bar:

           ALTER VIEW foo RENAME TO bar;

       To attach a default column value to an updatable view:

           CREATE TABLE base_table (id int, ts timestamptz);
           CREATE VIEW a_view AS SELECT * FROM base_table;
           ALTER VIEW a_view ALTER COLUMN ts SET DEFAULT now();
           INSERT INTO base_table(id) VALUES(1);  -- ts will receive a NULL
           INSERT INTO a_view(id) VALUES(2);  -- ts will receive the current time

COMPATIBILITY

       ALTER VIEW is a PostgreSQL extension of the SQL standard.

SEE ALSO

       CREATE VIEW (CREATE_VIEW(7)), DROP VIEW (DROP_VIEW(7))