Flink SQL update-mode set to retract in env file.

[srikanth flink]

How could I configure environment file for Flink SQL, update-mode: retract?

I have this for append:
properties:
        - key: zookeeper.connect
          value: localhost:2181
        - key: bootstrap.servers
          value: localhost:9092
        - key: group.id
          value: reconMultiAttempFail
    format:
      type: json
      fail-on-missing-field: false
      json-schema: >
        {
          type: 'object',
          properties: {
            'a': {
               type: 'string'
            },
            'b': {
               type: 'string'
            },
            'cnt': {
               type: 'string'
            }
          }
        }
      derive-schema: false

    schema:
      - name: 'a'
        type: VARCHAR
     - name: 'b'
        type: VARCHAR
      - name: 'cnt'
        type: BIGINT

Couldn't find any document for the same.

someone help me with the syntax.

Thanks
Srikanth