@Override
    protected Type visitExpression(Expression node, StackableAstVisitorContext<Context> context) {
      throw new SemanticException(
          String.format("not yet implemented: %s", node.getClass().getName()));
    }
@return the common supertype between the value type and subquery type
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/analyzer/ExpressionAnalyzer.java