public List<T> lookup(RowData lookupKey) {
    checkErrorAndRethrow();
    try {
      return kvTable.get(lookupKey);
    } catch (Exception e) {
      throw new FlinkRuntimeException(e);
    }
  }
Initialize the mixed-format table, kvTable and incrementalLoader.

@param context
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/lookup/BasicLookupFunction.java