Cassandra cannot parse ‘my_key’ as hex bytes

If you have “cannot parse ‘whatever_my_key’ as hex bytes” when you try to query Cassandra for some data, as in example below:

[code language=”bash”]
[default@CassandraCluster] get ServerLog[‘my_key’] limit 10;
org.apache.cassandra.db.marshal.MarshalException: cannot parse ‘my_key’ as hex bytes

then you must set the client-side encoding with assume command:

[code language=”bash”]
[default@CassandraCluster] assume ServerLog keys as utf8;


  1. What about actually teaching Cassandra what’s the type of the key for that column?

    update column family ServerLog with key_validation_class=UTF8Type;

    I think this will clear up all doubts for Cassandra

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