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Warning:
As of November 18, 2022, CockroachDB v21.1 is no longer supported. For more details, refer to the Release Support Policy.
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 name of a view withALTER VIEW ... RENAME TO
, the user must also have theDROP
privilege on the view.
Syntax
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 |
New in v21.1: 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:
> CREATE VIEW money_rides (id, revenue) AS SELECT id, revenue FROM rides WHERE revenue > 50;
> 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)
> ALTER VIEW money_rides RENAME TO expensive_rides;
RENAME VIEW
> 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:
> 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:
> CREATE SCHEMA IF NOT EXISTS cockroach_labs;
Then, change the view's schema:
> ALTER VIEW expensive_rides SET SCHEMA cockroach_labs;
> SHOW CREATE public.expensive_rides;
ERROR: relation "public.expensive_rides" does not exist
SQLSTATE: 42P01
> 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)