When serializing data in CSV or Avro formats, Stream Analytics optionally allows you to provide the schema. For CSV, the ...

When serializing data in CSV or Avro formats, Stream Analytics optionally allows you to provide the schema.
For CSV, the schema is represented as a comma-separated list of fields,  :  pairs, describing the data types associated with the record fields. Note: You can find the list of supported Stream Analytics data types in the link below.
For Avro, the Avro schema declaration is submitted.