Single Keyspace or Multiple Keyspace in cassandra datamodel

Question

Which one is best for managing data by using single keyspace or Multiple Keyspace , Suppose one application having more number of clients. Each client will send large set of data and we are storing data in time series column If i go for individual keyspace for every client, Will it be good in Cassandra for managing data? what are the advantages and disadvantages if i use one keyspace for one client in my application?

Answer 1

The main reason for having multiple keyspaces is because some settings are per keyspace, whereas some are per column family.

The most important per keyspace settings are for replication - replication strategy (single or multi DC) and replication factor (overall or per DC). All column families within a keyspace have the same replication settings. Different applications may have different replication requirements - maybe not today but may in the future. So for this reason it is a good idea to use different keyspaces for different applications.

In terms of performance or resource usage, it makes very little difference whether column families are in the same keyspace.