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> Documentation for ALTER NAMED COLLECTION

# ALTER NAMED COLLECTION

This query intends to modify already existing named collections.

<Note>
  DDL-created named collections can be enabled on select ClickHouse Cloud services. Contact Support to confirm availability.
</Note>

**Syntax**

```sql theme={null}
ALTER NAMED COLLECTION [IF EXISTS] name [ON CLUSTER cluster]
[ SET
key_name1 = 'some value' [[NOT] OVERRIDABLE],
key_name2 = 'some value' [[NOT] OVERRIDABLE],
key_name3 = 'some value' [[NOT] OVERRIDABLE],
... ] |
[ DELETE key_name4, key_name5, ... ]
```

**Example**

```sql theme={null}
CREATE NAMED COLLECTION foobar AS a = '1' NOT OVERRIDABLE, b = '2';

ALTER NAMED COLLECTION foobar SET a = '2' OVERRIDABLE, c = '3';

ALTER NAMED COLLECTION foobar DELETE b;
```

**Part of:** `ALTER`

**Related:** `CREATE NAMED COLLECTION`, `ALTER`, `DROP`