ASP form to check weather a form value is already in the database

    do while not objRS.EOF
        if rs("username")=Username then ' this will check if the entered username has already exist in the database
            set objRS=nothing
            set objConn=nothing
            Response.Redirect("UserNameAlreadyExist.asp")
        end if
        objRS.MoveNext
    loop

Dim Exists
Exists = false
Set objRS = objConn.Execute("SELECT * FROM accounts WHERE user = <%=UserName%>")
    do while not objRS.EOF
        Exists = true
        objRS.MoveNext
    loop
    set objRS=nothing
    set objConn=nothing

ELSE IF Exists
'Enter code to deal with trying to enter a username that already exists
ELSE
'Enter the code you already have for adding the account
END IF
END IF

 <%
 ' declare variables
Dim UserName
Dim Password
Dim Email

 ' get posted data into variables
UserName = Trim(Request.Form("UserName")) 
Password = Trim(Request.Form("Password")) 
Email = Trim(Request.Form("Email")) 

 ' validation
Dim validationOK
validationOK=true

If (Trim(UserName)="") Then
     validationOK=false
Else If (Trim(Password)="") Then
     validationOK=false
Else If (Trim(Email)="") Then
     validationOK=false
Else IF (Trim(UserName)="EOF" or Trim(Password)="EOF" or Trim(Email)="EOF") Then
     validationOK=false & response.write("If you have entered <strong>EOF</strong> in any of the fields then.<br>")

Else If (validationOK=false) Then 
     Response.write("Please go back fill in all ")
     Response.write("the requied information<br>")
     Response.write("<a href=""signup.asp"">Click here</a> to return to the form.")

Else If
"create another database connection here to query all the data in your database"
perform the validation as follow:

        do while not rs.EOF
       if rs("username")=Username Then
            set rs=nothing
            set conn=nothing
            Response.Redirect("username_duplicated.asp")
        end if
        rs.MoveNext
        loop
       
        Else   
          
          'Add account to Database
 Dim sConnection, objConn , objRS , strSQL
sConnection = "DRIVER={MySQL ODBC 3.51 Driver}; SERVER=localhost; DATABASE=xxxx; UID=xxxx;PASSWORD=xxxx; OPTION=3" 
Set objConn = Server.CreateObject("ADODB.Connection") 
objConn.Open(sConnection) 
Set objRS = objConn.Execute("INSERT INTO accounts (user,password,email ) VALUES ('" & username & "','" & password & "','" & email & "')")
'Response.Redirect("index.asp")
Response.write("<h2>Account Added!</h2>")
Response.write("Account: " & UserName & "<BR>")
Response.write("Password: " & Password & "<BR>")
Response.write("Email: " & Email)
End If
    %>