Solved

Retrieving a Max value from a table and storing in VB.net

Posted on 2007-11-16
5
837 Views
Last Modified: 2013-11-26
My SQL statement looks like this
select max(SEQ_NO) AS expr1 where fld1 = 'strFld1'.  According to the data this should return a number from 01 to 99, or null.  I can execute the query separate from the program and it works.  I need to know how to return the single value to process it.  I am used to returning the values to a dataset and placing in a grid.  I have 2 problems:  It is reurning a 0 or null that produces an error when I try to return it t to a dataset.  2nd.  How may I best refer to just one value returned from the query?  
0
Comment
Question by:garyinmiami2003
  • 4
5 Comments
 
LVL 63

Expert Comment

by:Fernando Soto
ID: 20304360
Can you post a section of code showing how you are attempting to get the results?
0
 
LVL 63

Accepted Solution

by:
Fernando Soto earned 500 total points
ID: 20304585
Hi garyinmiami2003;

Here is sample code using the Northwind database from SQL Server Express using the orders table and finding the max cost of shipping for customer HANAR.
Imports System.Data.SqlClient
 
        Dim connStr As String = "Data Source=localhost\sqlexpress; Initial Catalog=Northwind; Integrated Security=SSPI"
        Dim conn As New SqlConnection(connStr)
        Dim cmd As SqlCommand = conn.CreateCommand()
        cmd.CommandType = CommandType.Text
        cmd.CommandText = "SELECT MAX(Freight) AS exprt1 FROM Orders WHERE CustomerID = 'HANAR'"
        conn.Open()
        Dim money As Decimal = CDec(cmd.ExecuteScalar())
        conn.Close()
        MessageBox.Show(money.ToString("C"))

Open in new window

0
 
LVL 63

Expert Comment

by:Fernando Soto
ID: 20304607
Hi garyinmiami2003;

Your SQL select statement needs a FROM clause to identify the table

select max(SEQ_NO) AS expr1 FROM TableName where fld1 = 'strFld1'

Fernando
0
 

Author Comment

by:garyinmiami2003
ID: 20307396
Dim money As Decimal = CDec(cmd.ExecuteScalar())


Was the statement I needed.  Fernando, Thanks again for the high quality assistance
0
 
LVL 63

Expert Comment

by:Fernando Soto
ID: 20307520
Not a problem, glad I was able to help. ;=)
0

Featured Post

Master Your Team's Linux and Cloud Stack!

The average business loses $13.5M per year to ineffective training (per 1,000 employees). Keep ahead of the competition and combine in-person quality with online cost and flexibility by training with Linux Academy.

Question has a verified solution.

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

IP addresses can be stored in a database in any of several ways.  These ways may vary based on the volume of the data.  I was dealing with quite a large amount of data for user authentication purpose, and needed a way to minimize the storage.   …
Many of us here at EE write code. Many of us write exceptional code; just as many of us write exception-prone code. As we all should know, exceptions are a mechanism for handling errors which are typically out of our control. From database errors, t…
With Secure Portal Encryption, the recipient is sent a link to their email address directing them to the email laundry delivery page. From there, the recipient will be required to enter a user name and password to enter the page. Once the recipient …
I've attached the XLSM Excel spreadsheet I used in the video and also text files containing the macros used below. https://filedb.experts-exchange.com/incoming/2017/03_w12/1151775/Permutations.txt https://filedb.experts-exchange.com/incoming/201…

821 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