Using collections 

Collection types provide an improved way of handling tasks, such as building multiple email address capability into tables.

Apache Cassandra™ includes collection types that provide an improved way of handling tasks, such as building multiple email address capability into tables. Observe the following limitations of collections:

  • The maximum size of an item in a collection is 64K or 2B, depending on the native protocol version.
  • Keep collections small to prevent delays during querying because Cassandra reads a collection in its entirety. The collection is not paged internally.

    As discussed earlier, collections are designed to store only a small amount of data.

  • Never insert more than 64K items in a collection.

    If you insert more than 64K items into a collection, only 64K of them will be queryable, resulting in data loss.

Note: For detailed limits on collections, see CQL limits.

You can expire each element of a collection by setting an individual time-to-live (TTL) property.