Apache Cassandra 1.1 Documentation

ALTER KEYSPACE

This document corresponds to an earlier product version. Make sure you are using the version that corresponds to your version.

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Change attributes of a keyspace.

Synopsis

ALTER KEYSPACE <ks_name>
  WITH strategy_class = <value>
  [ AND strategy_options:<option> = <value> [...]
  [ AND durable_writes = true | false ] ];

Description

You can use ALTER KEYSPACE in Cassandra 1.1.6 and later to change the keyspace attributes:

You cannot change the name of the keyspace. The ALTER KEYSPACE statement must include setting the strategy class even when there is no change to the strategy class.

Example

Continuing with the last example in CREATE KEYSPACE, change the definition of the MyKeyspace keyspace to set durable_writes to false for purposes of this example. Changing the durable_writes attribute is not recommended because it could result in data loss.

Note

These examples work with pre-release CQL 3 in Cassandra 1.1.x. The syntax differs in the release version of CQL 3 in Cassandra 1.2 and later.

ALTER KEYSPACE "MyKeyspace"
  WITH strategy_class = NetworkTopologyStrategy
  AND durable_writes = false;

Check the keyspace settings:

SELECT * from system.schema_keyspaces;

The output describes the defined keyspace and looks something like this:

 keyspace   | durable_writes | name       | strategy_class          | strategy_options
------------+----------------+------------+-------------------------+------------------
 MyKeyspace |          False | MyKeyspace | NetworkTopologyStrategy |

CQL Commands

CQL Commands CQL Shell Commands
ALTER TABLE ASSUME
ALTER KEYSPACE CAPTURE
BATCH COPY
CREATE TABLE DESCRIBE
CREATE INDEX EXIT
CREATE KEYSPACE SHOW
DELETE SOURCE
DROP TABLE  
DROP INDEX  
DROP KEYSPACE  
INSERT  
SELECT  
TRUNCATE  
UPDATE  
USE