Drop Keyspace

In Cassandra, a keyspace is a namespace that defines how data is replicated and distributed over a cluster. Dropping a keyspace deletes all data stored in it and all tables within it.

Syntax

The syntax for dropping a keyspace in Cassandra is as follows:

DROP KEYSPACE [IF EXISTS] keyspace_name;

• IF EXISTS is an optional clause that only drops the keyspace if it exists.
• keyspace_name is the name of the keyspace that you want to drop.

Example

Suppose we have a keyspace called "my_keyspace" that we want to drop. We can use the following CQL statement to drop the keyspace:

DROP KEYSPACE IF EXISTS my_keyspace;

Output

If the keyspace exists, the output of the above statement would be simply "OK". If the keyspace does not exist, no action is taken.

Explanation

The DROP KEYSPACE statement is used to remove a keyspace from the Cassandra cluster. If the keyspace does not exist, the command does nothing, unless the IF EXISTS clause is used, in which case the command will not return an error or warning message.

Use

The main use case for dropping a keyspace is to delete all data stored within it, including all tables and other objects. This may be necessary if the keyspace is no longer needed or if it needs to be recreated with different replication or consistency settings, for example.

Important Points

• Dropping a keyspace deletes all data stored within it, including all tables.
• Use the IF EXISTS clause to avoid errors if the keyspace does not exist.
• Once a keyspace is dropped, it cannot be recovered unless a backup has been made.

Summary

In this tutorial, we learned about dropping a keyspace in Cassandra. We saw the syntax and example of DROP KEYSPACE statement and its output. Dropping a keyspace deletes all data stored within it, including all tables and other objects. This may be necessary in some cases, for example to delete an unused keyspace or to recreate it with different settings.