ALTER VIEW

The ALTER VIEW statement applies a schema change to a view.

Note:

This statement performs a schema change. For more information about how online schema changes work in CockroachDB, see Online Schema Changes.

Required privileges

  • To alter a view, the user must have the CREATE privilege on the parent database.
  • To change the schema of a view with ALTER VIEW ... SET SCHEMA, or to change the database of a view with ALTER VIEW ... RENAME TO, the user must also have the DROP privilege on the view.

Syntax

ALTER MATERIALIZED VIEW IF EXISTS view_name RENAME TO view_name SET SCHEMA schema_name OWNER TO role_spec

Parameters

Parameter Description
MATERIALIZED Rename a materialized view.
IF EXISTS Rename the view only if a view of view_name exists; if one does not exist, do not return an error.
view_name The name of the view to rename. To find view names, use:

SELECT * FROM information_schema.tables WHERE table_type = 'VIEW';
RENAME TO view_name Rename the view to view_name, which must be unique to its database and follow these identifier rules. Name changes do not propagate to the table(s) using the view.

Note that RENAME TO can be used to move a view from one database to another, but it cannot be used to move a view from one schema to another. To change a view's schema, use ALTER VIEW ...SET SCHEMA instead. In a future release, RENAME TO will be limited to changing the name of a view, and will not have the ability to change a view's database.
SET SCHEMA schema_name Change the schema of the view to schema_name.
OWNER TO role_spec Change the owner of the view to role_spec.

Limitations

CockroachDB does not currently support:

  • Changing the SELECT statement executed by a view. Instead, you must drop the existing view and create a new view.
  • Renaming a view that other views depend on. This feature may be added in the future (see tracking issue).

Examples

Rename a view

Suppose you create a new view that you want to rename:

icon/buttons/copy
> CREATE VIEW money_rides (id, revenue) AS SELECT id, revenue FROM rides WHERE revenue > 50;
icon/buttons/copy
> SELECT * FROM [SHOW TABLES] WHERE type = 'view';
  schema_name | table_name  | type | owner | estimated_row_count | locality
--------------+-------------+------+-------+---------------------+-----------
  public      | money_rides | view | demo  |                   0 | NULL
(1 row)
icon/buttons/copy
> ALTER VIEW money_rides RENAME TO expensive_rides;
RENAME VIEW
icon/buttons/copy
> SELECT * FROM [SHOW TABLES] WHERE type = 'view';
  schema_name |   table_name    | type | owner | estimated_row_count | locality
--------------+-----------------+------+-------+---------------------+-----------
  public      | expensive_rides | view | demo  |                   0 | NULL
(1 row)

Change the schema of a view

Suppose you want to add the expensive_rides view to a schema called cockroach_labs:

By default, unqualified views created in the database belong to the public schema:

icon/buttons/copy
> SHOW CREATE public.expensive_rides;
        table_name       |                                                 create_statement
-------------------------+-------------------------------------------------------------------------------------------------------------------
  public.expensive_rides | CREATE VIEW public.expensive_rides (id, revenue) AS SELECT id, revenue FROM movr.public.rides WHERE revenue > 50
(1 row)

If the new schema does not already exist, create it:

icon/buttons/copy
> CREATE SCHEMA IF NOT EXISTS cockroach_labs;

Then, change the view's schema:

icon/buttons/copy
> ALTER VIEW expensive_rides SET SCHEMA cockroach_labs;
icon/buttons/copy
> SHOW CREATE public.expensive_rides;
ERROR: relation "public.expensive_rides" does not exist
SQLSTATE: 42P01
icon/buttons/copy
> SHOW CREATE cockroach_labs.expensive_rides;
            table_name           |                                                     create_statement
---------------------------------+---------------------------------------------------------------------------------------------------------------------------
  cockroach_labs.expensive_rides | CREATE VIEW cockroach_labs.expensive_rides (id, revenue) AS SELECT id, revenue FROM movr.public.rides WHERE revenue > 50
(1 row)

See also

YesYes NoNo