Over a million developers have joined DZone.

Indexing JSON in Cassandra

· Java Zone

Discover how powerful static code analysis and ergonomic design make development not only productive but also an enjoyable experience, brought to you in partnership with JetBrains


Cassandra has native indexing capabilities, but those capabilities only work if the values stored in your columns are the values you want indexed.  If the data is structured in some way (e.g. JSON or Protobuf), it is impossible to leverage Cassandra's indexing capabilities out of the box.

A while back we had a discussion on the dev list regarding indexing attributes stored in columns in Cassandra.  I think Jermiah Jordan had the best description of the problem.  Lately, we found ourselves with the same problem so we ended up building it into our cassandra-indexing extension.

Our cassandra-indexing module, is an AOP-based extension to Cassandra.  Drop the jar file in the Cassandra lib directory, update the start script to include the extension and the aspect will take care of indexing information as you mutate the data in Cassandra.

To support indexing a specific field within the column value, we added the ability for a user to specify a field to index (not just a column name).  We then parse the JSON document as it is written in the mutation, extract the values and create entries in the wide-row index for that column family.

Specifics for the new JSON-based indexing configuration can be found on the wiki.  Admittedly, we are still light on documentation.  If you have any trouble using the new capability, let us know.

Learn more about Kotlin, a new programming language designed to solve problems that software developers face every day brought to you in partnership with JetBrains.

Topics:

Published at DZone with permission of Brian O' Neill, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

The best of DZone straight to your inbox.

SEE AN EXAMPLE
Please provide a valid email address.

Thanks for subscribing!

Awesome! Check your inbox to verify your email so you can start receiving the latest in tech news and resources.
Subscribe

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}