public static boolean isDdlRecord(Struct value) {
        return value.schema().field(HISTORY_RECORD_FIELD) != null;
    }
Whether the source Record is a schema change event.
@param sourceRecord
@return ture if the source Record is a schema change event.
inlong-sort/sort-flink/cdc-base/src/main/java/org/apache/inlong/sort/cdc/base/util/RecordUtils.java