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Editorial Team
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Asked: 2026-05-16T20:30:52+00:00

I am trying to develop a page to display student/class results by subject/teacher. Some

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I am trying to develop a page to display student/class results by subject/teacher.

Some classes have groups which contain students and some have only students. A subject is thought by one or more teachers. This may change in the future and I want to keep the design as flexible as possible (i.e. subjects might be broken into modules or into individual test results, classes might be further grouped by year etc)

I want to display the end results in a grid that I can expand and roll up to average out the results (class on the Y and subject on the X).

My though it to have 3 database tables as follows:

**class_structure**
id (int) PK
description (varchar)
parent_id (int) FK to id

The highest level would be the class (with no parent id) and the lowest level would be the student.

**subject_structure**
id (int) PK
description (varchar)
parent_id (int) FK to id

The highest level being the subject, lowest being the teacher

**results**
id (int) PK 
class_structure_id (int) FK
subject_structure_id (int) FK
date (datetime)
reult (int)

What do you think of the above structure? I believe this gives me flexibility going forward?

In my asp.net app then I query the highest class structure level and average out all the results below that (am I better to do this averaging in a sproc in the DB or use say LINQ in the app?)

This would give me back a set of results at the highest level.

Then I would need to display this is a table (i am thinking of just creating the table html in C#?) against the subject classes (i.e. create all the headers first and then try to place the result in the correct column (i am not sure how to do this though)).

<table border="1" padding="2">
 <tr>
  <td></td>
  <td></td>
  <td colspan="2" align="center">Subj 1</td>
  <td colspan="2" align="center">Subj 2</td>
 </tr>

 <tr>
  <td></td>
  <td></td>
  <td>Teacher 1</td>
  <td>Teacher 2</td>
  <td>Teacher 1</td>
  <td>Teacher 2</td>
 </tr>
 <tr>
  <td rowspan="2">Class 1</td>
  <td>Student 1</td>
  <td>90</td>
  <td>55</td>
  <td>75</td>
  <td>100</td>
 </tr>
 <tr>
  <td>Student 2</td>
  <td>40</td>
  <td>95</td>
  <td>65</td>
  <td>39</td>
 </tr>
</table>

Then when the user clicked on the first class, this would expand out and show all the groups (if any, students if not) (pass the class_structure_id of the clicked cell to the same method/sproc and get those results) and then redraw the table with an extra column.

Is this a good way to go about achieving what I am trying to do?

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1 Answer

  1. Editorial Team

    1:) Hierarchical data should not be displayed in a <table>, use nested <ul> or <ol> instead. Tables are for tabular data.

    2:) Since c# is an object oriented language, I would not reference the objects in the tree by an Id. Why not add a collection of child objects as a member a sample code pattern would be:

    class TreeElement 
{
 public TreeElement Parent {get;}
 public IEnumerable<TreeElement> Children{get;};
 public AddChild(TreeElement element }
 public bool IsRoot { return Parent == null; }
 public bool IsLeaf { return Children.Length == 0; }
 public bool IsBranch {return !IsRoot && !IsLeaf; }
}

    normally in a tree you don’t want to do a parent lookup. So if not needed leave all the parent references to avoid useless complexity 😉
    Try to insert stuff in the database in an object structure like above.

    3:) Key lookup according to your model will go eventually very slow in SQL. You ‘ll have to loop trough data and use if/else statements in your query
    On SQLTeam is a great sample on how to make that very fast with the use of an extra lineage column.

    4:) Use linq to query and generate the results for your data.

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