How to drop all Tables and UDTs from a Cassandra Keyspace?

Question

Is there any way to clear a keyspace in Cassandra? We cannot drop the keyspace directly, as we don't have rights to create or drop keyspaces. Thank you in advance!

PS we are using Cassandra 3.7.

Answer 1

You can do something like cqlsh -e 'use ;describe tables'. This will return a list of tables that you can use to create queries to delete those tables. Similar with udt's.

Answer 2

Implementing it via cqlsh is quite straightforward, and it's better than try to implement something using the custom code - there are nuances of the programmatic schema changes, that it's better to avoid:

Full script to drop everything is here:

cqlsh -e 'describe keyspace test;' > ks.cql
rm -f drop-all.cql
grep -e '^CREATE MATERIALIZED VIEW' ks.cql|sed -e 's|^CREATE MATERIALIZED VIEW \(.*\) ($|DROP MATERIALIZED VIEW \1;|' >> drop-all.cql
grep -e '^CREATE INDEX' ks.cql|sed -e 's|^CREATE INDEX \(.*\) ($|DROP INDEX \1;|' >> drop-all.cql
grep -e '^CREATE TABLE' ks.cql|sed -e 's|^CREATE TABLE \(.*\) ($|DROP TABLE \1;|' >> drop-all.cql
grep -e '^CREATE TYPE' ks.cql|sed -e 's|^CREATE TYPE \(.*\) ($|DROP TYPE \1;|' >> drop-all.cql
cqlsh -f drop-all.cql