Writing a Parent-Child Query Sorter in CF, Part 1

Oct 11

Table of contents for CFTreeQuerySort

  1. Writing a Parent-Child Query Sorter in CF, Part 1
  2. Writing a Parent-Child Query Sorter in CF, Part 2
  3. Writing a Parent-Child Query Sorter in CF, Part 3
  4. Writing a Parent-Child Query Sorter in CF, Part 4
  5. Writing a Parent-Child Query Sorter in CF, Part 5
  6. Writing a Parent-Child Query Sorter in CF, Part 6
  7. Writing a Parent-Child Query Sorter in CF, Part 7
  8. Writing a Parent-Child Query Sorter in CF, Part 8
  9. Writing a Parent-Child Query Sorter in CF, Part 9
  10. Writing a Parent-Child Query Sorter in CF, Part 10
  11. Writing a Parent-Child Query Sorter in CF, Part 11
  12. Parent-Child Queries Enhancement: Stacked Numbering
  13. Parent-Child Queries Enhancement: Multi-Parented Items
  14. Tree Query Sorter series now available as PDF
One of the Stupid-Web-Programming-Tricks I end up recoding quite often is a sorter for queries with Parent-Child relationships. Trees, basically. You know the situation: some yahoo wants theoretically infinite levels of depth to his navigational menus or his product categories for his e-commerce system. What you end up with is a table in a database that looks like this:
Stuff
ItemID Title ParentID
12Coding0
26Web12
15Applications12
9Hybrid12
7Food0
8C++15
19Perl9
16ColdFusion26
1Cheese7
This should magically yield a list that looks like this:
  1. Coding
    1. Applications
      1. C++
    2. Hybrid
      1. Perl
    3. Web
      1. ColdFusion
  2. Food
    1. Cheese
Getting from Point A to Point B isn’t all that hard, especially when you have the time, foresight, and ability to plan ahead. There are dozens of different ways to accomplish this efficiently within the database. Most of the time, however, I find that I have read-only access to the database table and end up having to do the organization in code. In this series of posts I’ll be explaining my solution and how I get to it.
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