protected void fillRetractField(Row row, boolean change) {
		root.put(retractKey, change);
		CsvSchema.Builder newBuilder = new CsvSchema.Builder(csvSchema);

		CsvSchema.Column retractColumn = new CsvSchema.Column(row.getArity(), retractKey, CsvSchema.ColumnType.BOOLEAN);
		newBuilder.addColumn(retractColumn);
		csvSchema = newBuilder.build();

		this.objectWriter = csvMapper.writer(csvSchema);

	}
Creates a {@link CsvRowSerializationSchema} expecting the given {@link TypeInformation}.

@param typeInfo type information used to create schema.
kafka-base/kafka-base-sink/src/main/java/com/dtstack/flink/sql/sink/kafka/serialization/CsvTupleSerializationSchema.java