How do I delete all data in a Cassandra column family?

Question

I\'m looking for a way to delete all of the rows from a given column family in cassandra.

This is the equivalent of TRUNCATE TABLE in SQL.

Answer 1

if you are working on cluster setup, truncate can only be used when all the nodes of the cluster are UP.

By using truncate, we will miss the data(we are not sure with the importance of the data)

So the very safe way as well a trick to delete data is to use COPY command,

1) backup data using copy cassandra cmd
copy tablename to 'path'

2) duplicate the file using linux cp cmd
cp 'src path' 'dst path'

3) edit duplicate file in dst path, delete all lines expect first line.
save the file.

4) use copy cassandra cmd to import
copy tablename from 'dst path'