I don't believe it is currently possible to convert/use the decimal type in the Avro processors, I have written up NIFI-3000 to cover this improvement. If you are comfortable with a scripting language like Javascript or Groovy, you could use the ExecuteScript processor, point the Module Directory property at JAR(s) for Avro 1.8.0, and code the conversion yourself. However beware that you don't do additional Avro processing downstream, as that will likely break (because of the bug in NIFI-3000). ... View more