Using an Include File For Database Connectivity

I’ve found that many ASP developers don’t like repetitive tasks, yet many developers
do the following: on each page using database connectivity, they write the following
code:

Click here for code example 1.

Now why write all of this? First off, is a Session variable really needed here?
No. Should we have to retype all of this on each page we want to have database
connectivity? No. A simpler solution is to use an include file, which contains
the above lines (and the connection string hard coded in).

Let’s say we do this in a file named dbConn.asp, and put it in our
/scripts directory. dbConn.asp might look something like
this:

Click here for code example 2.

Then, in every page we want to use database connectivity, we just need to add
this one line:

Click here for code example 3.

Isn’t this way much easier? Whenever we need to refer to a database connection
object (such as in the Open method of the recordset object, we simply
use objConn, the name of the connection object in dbConn.asp.

From alert 4Guys visitor Steven D.:

While this tip is indeed useful, it is not always necessary to make a
connection to the database every time you hit that page. I have a method
that allows more flexibility.

In sites that I have built, I have always wrapped my database connection
code in an IF statement and check for a querystring variable that
determines if I should use the database connection or not. Example (inside
the datbase include file):

if request("connect") = "true" then

  connection stuff......

end if

This saves connections and allows me to include the database include file
in a global include so it’s always there if I need it.

For more information on include files, read Using Includes.
For more information on database connections, read Database Connectivity. Happy Programming!

This tip originally appeared in the Web Technology section of 4GuysFromRolla.com.