How can I Update Multiple Rows in my Database from Form Checkboxes?

The Situation: You have a form that returns a comma-delimited list of values. For example...

<input type="checkbox" name="userSkills" value="CF">ColdFusion
<input type="checkbox" name="userSkills" value="JS">Javascript
<input type="checkbox" name="userSkills" value="Flash">Flash
<input type="checkbox" name="userSkills" value="HS">Homesite/Studio
<input type="checkbox" name="userSkills" value="Smalltalk">Smalltalk
<input type="checkbox" name="userSkills" value="Java">Java

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Let's say that you have a table in your database called "UserSkills" that has a composite primary key made up of (1)a userID and (2)a skill. When this form is sent to you, you are going to get a comma-delimited list of user skills -- unless of course, the user doesn't click any checkboxes, in which case you'll need some error-handling code!

What to do with the comma-delimited list? Some items may be new, while others in the database may not reflect the updated list provided by the user.

The Solution: One way to handle this is to use a two step process. First you delete all the existing rows in that database and then you insert new ones. The code would look something like this:

<cfquery name="deleteItems" datasource="aDatasource">
 DELETE * FROM myTable WHERE userID = '#userID#'
</cfquery>
 
<cfloop list="#form.userSkills#" index="aSkill">
 <cfquery datasource="aDatasource" name="insertItems">
   INSERT INTO myTable(userID, skill)
   VALUES('#userID#','#aSkill#')
 </cfquery>
</cfloop>