How to convert Cassandra TimeUUID stored in the TEXT field to a TimeStamp in cql?

The Akka Projection library stores TimeUUID values as TEXT in the offset_store table. When you query the offset from the offset_store table, it shows the UUID string. It would be nice if it could be converted to a human-readable timestamp. Unfortunately, after hours of fruitless googling, I decided to create my own UDF (User-Defined Function) in Cassandra to make the conversation possible.

First, let’s look at the schema of the Akka Projection offset storage table in Cassandra;

The column we are interested in is offset .

Second, let’s create the UDF in Cassandra;

  • By default, Cassandra disables user defined functions. You can enable it by editing cassandra.yaml. Remember to restart your Cassandra;
  • Now we are ready to create our own function: textToTimestamp

Finally, we are ready to use the UDF that was just created in a cql SELECT statement;

textToTimestamp

Here you go, you can easily see the timestamp of the offset column.

If you know any other way of converting TimeUUID stored in the TEXT column to a human-readable format in cql, please comment below.

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