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title: "ALTER ... RENAME" description: "ALTER ... RENAME renames an item." menu: main:

parent: 'commands'

ALTER ... RENAME renames an item, albeit with some limitations.

Note that renaming databases is not supported {{% gh-discussion 29635 %}}.

Syntax

Field	Use
name	The identifier of the item you want to rename.
new_name	The new identifier you want the item to use.

Because of Materialize's SQL engine, we currently only support renaming items in limited contexts.

You cannot rename items if:

They are not uniquely qualified among all references to their identifier in all dependent views.

For example, if you have:
- Two views named v1 in two different databases (d1, d2), but they both use the same schema name (s1)
- Both views named v1 are used in another view's query
You can only rename either view named v1 if every dependent view's query that contains references to both views fully qualifies all references, e.g.
```
CREATE VIEW v2 AS
SELECT *
FROM db1.s1.v1
JOIN db2.s1.v1
ON db1.s1.v1.a = db2.s1.v1
```
If these two views were placed in schemas using distinct identifiers, you would only need to qualify their references with schemas instead of databases and schemas.
Any dependent query references a database, schema, or column that uses the same identifier.

In the following examples, v1 could not be renamed:
```
CREATE VIEW v3 AS
SELECT *
FROM v1
JOIN v2
ON v1.a = v2.v1
```
```
CREATE VIEW v4 AS
SELECT *
FROM v1
JOIN v1.v2
ON v1.a = v2.a
```
They are system clusters, such as mz_system and mz_catalog_server, or replicas in system clusters.

You cannot rename an item to any identifier used in a dependent query, whether that identifier is used implicitly or explicitly.

Consider this example:

CREATE VIEW v5 AS
SELECT *
FROM d1.s1.v2
JOIN v1
ON v1.a = v2.b

You could not rename v1 to:

a
b
v2
s1
d1
materialize or public (implicitly referenced by materialize.public.v1 using the default database and schema)

However, you could rename v1 to any other legal identifier.

SHOW VIEWS;

 VIEWS
-------
 v1

ALTER VIEW v1 RENAME TO v2;
SHOW VIEWS;

 VIEWS
-------
 v2

The privileges required to execute this statement are:

{{< include-md file="shared-content/sql-command-privileges/alter-rename.md" >}}