Keyspace¶

Creating a Keyspace (CREATE KEYSPACE)¶

To start a CREATE KEYSPACE query, use createKeyspace in SchemaBuilder:

import static com.datastax.oss.driver.api.querybuilder.SchemaBuilder.*;

CreateKeyspaceStart create = createKeyspace("cycling");

Like all other CREATE queries, one may supply ifNotExists() to require that the keyspace should only be created if it doesn’t already exist, i.e.:

CreateKeyspaceStart create = createKeyspace("cycling").ifNotExists();

Note that, at this stage, the query cannot be completed yet. You need to provide at least a replication strategy. The two most widely used ones are SimpleStrategy and NetworkTopologyStrategy.

To provide a replication strategy, use one of the following API methods on CreateKeyspaceStart:

• withSimpleStrategy(int replicationFactor)

• withNetworkTopologyStrategy(Map<String, Integer> replications)

• withReplicationOptions(Map<String, Object> replicationOptions)

For example, the following builds a completed CreateKeyspace using NetworkTopologyStrategy with a replication factor of 2 in east and 3 in west:

CreateKeyspace create = createKeyspace("cycling")
    .withNetworkTopologyStrategy(ImmutableMap.of("east", 2, "west", 3));
// CREATE KEYSPACE cycling WITH replication={'class':'NetworkTopologyStrategy','east':2,'west':3}

Optionally, once a replication factor is provided, one may provide additional configuration when creating a keyspace:

• withDurableWrites(boolean durableWrites)

• withOption(String name, Object value)

Altering a Keyspace (ALTER KEYSPACE)¶

To start an ALTER KEYSPACE query, use alterKeyspace:

AlterKeyspaceStart alterKeyspace = alterKeyspace("cycling");

From here, you can modify the keyspace’s replication and other settings:

• withSimpleStrategy(int replicationFactor)

• withNetworkTopologyStrategy(Map<String, Integer> replications)

• withReplicationOptions(Map<String, Object> replicationOptions)

• withDurableWrites(boolean durableWrites)

• withOption(String name, Object value)

At least one of these operations must be used to return a completed AlterKeyspace, i.e.:

alterKeyspace("cycling").withDurableWrites(true);
// ALTER KEYSPACE cycling WITH durable_writes=true

Dropping a keyspace (DROP KEYSPACE)¶

To create a DROP KEYSPACE query, use dropKeyspace:

dropKeyspace("cycling");
// DROP KEYSPACE cycling

You may also specify ifExists:

dropKeyspace("cycling").ifExists();
// DROP KEYSPACE IF EXISTS cycling