private void checkIfJoinKeyTypeMatches(Type leftJoinKeyType, Type rightJoinKeyType) {
    if (leftJoinKeyType != rightJoinKeyType) {
      throw new SemanticException(
          "Join key type mismatch. Left join key type: "
              + leftJoinKeyType
              + ", right join key type: "
              + rightJoinKeyType);
    }
  }
This Visitor is responsible for transferring Table PlanNode Tree to Table Operator Tree.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/TableOperatorGenerator.java