public String getInputString(List<Expression> expressions) {
    StringBuilder builder = new StringBuilder();
    if (!(expressions.isEmpty())) {
      builder.append(expressions.get(0).getExpressionString());
      for (int i = 1; i < expressions.size(); ++i) {
        builder.append(", ").append(expressions.get(i).getExpressionString());
      }
    }
    appendAttributes(builder);
    return builder.toString();
  }
Generates the parameter part of the function column name.

<p>Example:

<p>Full column name -> udf(root.sg.d.s1, sin(root.sg.d.s1))

<p>The parameter part -> root.sg.d.s1, sin(root.sg.d.s1)
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/plan/parameter/AggregationDescriptor.java