docs/sql-ref-syntax-ddl-alter-database.md

---
layout: global
title: ALTER DATABASE
displayTitle: ALTER DATABASE
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---

### Description

`ALTER DATABASE` statement changes the properties or location of a database. Please note that the usage of
`DATABASE`, `SCHEMA` and `NAMESPACE` are interchangeable and one can be used in place of the others. An error message
is issued if the database is not found in the system.

### SET PROPERTIES
`ALTER DATABASE SET DBPROPERTIES` statement changes the properties associated with a database.
The specified property values override any existing value with the same property name. 
This command is mostly used to record the metadata for a database and may be used for auditing purposes.

#### Syntax

```sql
ALTER { DATABASE | SCHEMA | NAMESPACE } database_name
    SET { DBPROPERTIES | PROPERTIES } ( property_name = property_value [ , ... ] )
```

#### Parameters

* **database_name**

    Specifies the name of the database to be altered.

### UNSET PROPERTIES
`ALTER DATABASE UNSET DBPROPERTIES` statement unsets the properties associated with a database.
If the specified property key does not exist, the command will ignore it and finally succeed.
(available since Spark 4.0.0).

#### Syntax

```sql
ALTER { DATABASE | SCHEMA | NAMESPACE } database_name
    UNSET { DBPROPERTIES | PROPERTIES } ( property_name [ , ... ] )
```

#### Parameters

* **database_name**

  Specifies the name of the database to be altered.

### SET LOCATION
`ALTER DATABASE SET LOCATION` statement changes the default parent-directory where new tables will be added 
for a database. Please note that it does not move the contents of the database's current directory to the newly 
specified location or change the locations associated with any tables/partitions under the specified database 
(available since Spark 3.0.0 with the Hive metastore version 3.0.0 and later).

#### Syntax

```sql
ALTER { DATABASE | SCHEMA | NAMESPACE } database_name
    SET LOCATION 'new_location'
```

#### Parameters

* **database_name**

  Specifies the name of the database to be altered.

### Examples

```sql
-- Creates a database named `inventory`.
CREATE DATABASE inventory;

-- Alters the database to set properties `Edited-by` and `Edit-date`.
ALTER DATABASE inventory SET DBPROPERTIES ('Edited-by' = 'John', 'Edit-date' = '01/01/2001');

-- Verify that properties are set.
DESCRIBE DATABASE EXTENDED inventory;
+-------------------------+------------------------------------------+
|database_description_item|                database_description_value|
+-------------------------+------------------------------------------+
|            Database Name|                                 inventory|
|              Description|                                          |
|                 Location|   file:/temp/spark-warehouse/inventory.db|
|               Properties|((Edit-date,01/01/2001), (Edited-by,John))|
+-------------------------+------------------------------------------+

-- Alters the database to set a new location.
ALTER DATABASE inventory SET LOCATION 'file:/temp/spark-warehouse/new_inventory.db';

-- Verify that a new location is set.
DESCRIBE DATABASE EXTENDED inventory;
+-------------------------+-------------------------------------------+
|database_description_item|                 database_description_value|
+-------------------------+-------------------------------------------+
|            Database Name|                                  inventory|
|              Description|                                           |
|                 Location|file:/temp/spark-warehouse/new_inventory.db|
|               Properties| ((Edit-date,01/01/2001), (Edited-by,John))|
+-------------------------+-------------------------------------------+

-- Alters the database to unset the property `Edited-by`
ALTER DATABASE inventory UNSET DBPROPERTIES ('Edited-by');

-- Verify that the property `Edited-by` has been unset.
DESCRIBE DATABASE EXTENDED inventory;
+-------------------------+-------------------------------------------+
|database_description_item|                 database_description_value|
+-------------------------+-------------------------------------------+
|            Database Name|                                  inventory|
|              Description|                                           |
|                 Location|file:/temp/spark-warehouse/new_inventory.db|
|               Properties| ((Edit-date,01/01/2001))                  |
+-------------------------+-------------------------------------------+

-- Alters the database to unset a non-existent property `non-existent`
-- Note: The command will ignore 'non-existent' and finally succeed
ALTER DATABASE inventory UNSET DBPROPERTIES ('non-existent');
```

### Related Statements

* [DESCRIBE DATABASE](sql-ref-syntax-aux-describe-database.html)