This task has been successfully solved! The required Jolt construction is shown below.   [   {      "operation": "shift",      "spec": {        "*": {          "table_name": "&",          "*": "data[&1].&"        }      }   },   {       "operation": "cardinality",      "spec": {        "table_name": "ONE"      }   } ] ... View more

Thank you for your answer! All my json FlowFiles have a FlowFile attribute on them for "table_name". There may be a problem with the json schema itself. Now the task has changed. I have created a new question about Jolt. https://community.cloudera.com/t5/Support-Questions/Jolt-transform/td-p/330850   If you know the answer to it, I would be very grateful! ... View more