• Home
• Tutorials
• Forums
• Reference
• Developers
• Advertise
• About Us

Using Query String Values....

I was emailed earlier this week and asked if I could write a tutorial on how to insert data into a database with "query string" variables. 
[i.e. page.cfm?name=John&email=john@smith.com]

So I thought I would create a short tutorial demonstrating the use of different variables within a query.

The first thing you must remember is that a variable is a variable, whether it is being passes via a form or a URL query string. With that in mind I'll show you different ways that you can access variables.

Let's say you have a form that will allow a user to add their name and email to a database. You have to ways for passing the variables. The first example is the recommended way.

The first way to pass variables is via FORM submission. As seen below.

<!--- Form Page --->
<form action="process.cfm" method="post">
Name: <input type="text" name="myname"><BR>
Email: <input type="text" name="myemail"><BR>
<input type="submit" name="Go" value="Add Me">
</form>

What makes this form actually pass FORM variables is the method="post" defined in the <form> tag. So on the action page you would use the passed values and enter them into your database as follows:

<!--- Insert user --->
<cfquery name="qAddUser" datasource="MyDSN">
   INSERT INTO Users(
                              Name,
                              Email,
                             )
                    Values(
                               '#form.myname#',
                               '#form.myemail#',
                              )
</cfquery>

Notice that you are referring to the variables a form.variables. If you would remove the METHOD="POST" definition to the form page, then your form would be passed via URL query string variables. so using the #form.name# method wouldn't work, simply because they are no longer FORM variables, but instead URL Variables.

So, how do you reference URL variables? Well using URL.name of course :)

So if you have a URL quesrystring form then how would the <cfquery> above look then? Let's take a look:

<!--- Insert user --->
<cfquery name="qAddUser" datasource="MyDSN">
   INSERT INTO Users(
                              Name,
                              Email,
                             )
                    Values(
                               '#url.myname#',
                               '#url.myemail#',
                              )
</cfquery>

It's that simple. Now keep in mind that I don't personally suggest you use query string values. Simply because you'll have to pass the values in URL Encoded Format (What is URL Encoded Format?) which is just asking for trouble. Always use FORM variables, they're easier to work with and are always much more effective, not to mention they're also cross-browser [i.e Internet Explorer, Netscape, Opera, etc.] friendly :)

Well, there's also much more to this method (URL String values) such as URLEncodedFormat, URLDecode and more, If you are seriously looking to use URL formats, I suggest you familiarize yourself with these tags and their usage.