In this article, we are going to look at how to implement an Ajax solution that uses an ASP.NET page to pull data from a back-end database. In this tutorial, we have a table stored in a MySQL database.

You can replace the ASP.NET code on this page with any other server-side scripting languages that you are familiar with such as ASP or PHP. You can refer to the other tutorials in this series for more help using a different server-side scripting language.

In addition, the back-end data source does not have to be MySQL. You can modify the database connection in the example for accessing other database platforms. The concept remains the same.

HTML Example

Select an Employee for more details!

ASP.NET Example

Imports System.Data.Odbc

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

Response.AppendHeader("Cache-Control", "no-cache")
Response.AppendHeader("Cache-Control", "no-store")
Response.AppendHeader("Cache-Control", "must-revalidate")
Response.AppendHeader("Pragma", "no-cache")
Response.AppendHeader("Expires", "Sat, 14 Jan 2012 01:00:00 GMT")
    
Dim db_svr As String = "dbserver.com"
Dim db_name As String = "databaseName"
Dim db_un As String = "dbUserName"
Dim db_upwd As String = "dbPassword"
Dim tablename As String = "employees"
Dim fieldname1 As String = "empName"
Dim fieldname2 As String = "empTitle"
Dim fieldname3 As String = "empOffice"
Dim q As String = Request.QueryString("q")
Dim dbQuery As String = "SELECT * FROM " & tablename & " WHERE empID = " & q
    
    
Dim connStr = "Driver={MySQL ODBC 3.51 Driver};SERVER=" & db_svr & ";DATABASE=" & db_name & ";UID=" & db_un & ";PWD=" & db_upwd
Dim dbconn As OdbcConnection = New OdbcConnection(connStr)

Dim dbCommand As New OdbcCommand
dbCommand.Connection = dbConn
Try
    dbconn.Open()
    dbCommand.CommandText = dbQuery
    Dim reader = dbCommand.ExecuteReader()
    Response.Write("<table class='tblClear'>")
    Do While reader.Read() = True
        Response.Write("<tr><td style='width:100px;'>Name:</td><td>" & reader(fieldname1) & "</td></tr>")
        Response.Write("<tr><td style='width:100px;'>Name:</td><td>" & reader(fieldname2) & "</td></tr>")
        Response.Write("<tr><td style='width:100px;'>Name:</td><td>" & reader(fieldname3) & "</td></tr>")
    Loop
    dbconn.Close()
    Response.Write("</table>")

Catch ex As Exception
    Response.Write("An error occured trying to access the database.")
End Try

End Sub