Expiring Today—Celebrate National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

How can I make a recursive query?

Posted on 2008-06-11
3
Medium Priority
?
303 Views
Last Modified: 2013-11-26
Hello everybody,

I finally could populate a combobox in VB.NET with data grabbed from a remote MySQL DB. The problem is that that data, only fills the combobox but doesn't store the query results in an array or anything. What I need to do now, is to validate the selected user with the DB, while making the password MD5 hashed. This MD5 encrypt is easy, but I don't know why I can't make the second query to fetch the password for the selected user in the combobox (making a last name, first name comparation).

Here's my code:
Private Sub comUsername_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles comUsername.TextChanged
        If comUsername.Text <> "" Then
            txtPassword.Enabled = True
            Dim user_full_name As String
 
            user_full_name = comUsername.Text
 
            SQL2 = "SELECT user_id FROM users WHERE 'user_last_name, user_name' = @user_full_name"
            myCommand.Connection = conn
            myCommand.CommandText = SQL2
 
            myAdapter.SelectCommand = myCommand
            myAdapter.Fill(myData)
 
            oReader = myCommand.ExecuteReader
 
            selected_user_id = oReader("user_id")
 
            MsgBox(selected_user_id)
 
            oReader.Close()
 
        Else
            txtPassword.Text = ""
            txtPassword.Enabled = False
        End If
    End Sub

Open in new window

0
Comment
Question by:Cesar Aracena
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 
LVL 143

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 1000 total points
ID: 21771342
>            SQL2 = "SELECT user_id FROM users WHERE 'user_last_name, user_name' = @user_full_name"

you might look for the CONCAT function:
            SQL2 = "SELECT user_id FROM users WHERE CONCAT(user_last_name, ' ' , user_name) = @user_full_name"

assuming lastname and username as separated by a space.
0
 
LVL 6

Author Comment

by:Cesar Aracena
ID: 21771398
Thanks! It was that. it also had a comma (plus space). Another thing that I found is how to propperly place the variable in the SELECT statement:

SQL2 = "SELECT * FROM users WHERE concat(user_last_name,', ',user_name) = '" & comUsername.Text & "'"

Thanks agian!
0
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 21771446
>Another thing that I found is how to propperly place the variable in the SELECT statement:
using that method is NOT properly done.
use either the MySqlParameter, or at least handle the single quote "issue":

SQL2 = "SELECT * FROM users WHERE concat(user_last_name,', ',user_name) = '" & comUsername.Text.Replace("'", "''") & "'"

using the MySqlParameter:
http://dotnetnuke.adefwebserver.com/MySQL/MySql5sample/tabid/289/Default.aspx
0

Featured Post

Python: Series & Data Frames With Pandas

Learn the basics of Python’s pandas library of series & data frames and how we can use these tools for data manipulation.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article describes relatively difficult and non-obvious issues that are likely to arise when creating COM class in Visual Studio and deploying it by professional MSI-authoring tools. It is assumed that the reader is already familiar with the cla…
The ECB site provides FX rates for major currencies since its inception in 1999 in the form of an XML feed. The files have the following format (reducted for brevity) (CODE) There are three files available HERE (http://www.ecb.europa.eu/stats/exch…
This is my first video review of Microsoft Bookings, I will be doing a part two with a bit more information, but wanted to get this out to you folks.
Do you want to know how to make a graph with Microsoft Access? First, create a query with the data for the chart. Then make a blank form and add a chart control. This video also shows how to change what data is displayed on the graph as well as form…

719 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question