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06.01.2007 at 06:18AM PDT, ID: 22606886
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7.4

Null DB value

Asked by andyb7901 in Microsoft Visual Basic.Net, Visual Basic Programming

Tags: , ,

I have a query which checks the next ID in the DB. I have cleared my DB and ran the code. I get the error message;

Conversion from type 'DBNull' to type 'Integer' is not valid.

Does anyone know how I would adapt my code to check to see if the value is null and then react to it? My current code is;

Dim Sql As String = "SELECT Max([Problem_ID]) AS MaxOfOrderID, Max([Problem_ID])+1 AS NextID " & _
 " From tbl_Problems"
            Dim cmd As New OleDbCommand(Sql, conn)
            Dim dr As OleDbDataReader = cmd.ExecuteReader
            While dr.Read
                If dr.HasRows = False Then
                Else
                    NextID = dr.Item("NextID")
                End If
            End WhileStart Free Trial
[+][-]06.01.2007 at 06:25AM PDT, ID: 19194782

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[+][-]06.01.2007 at 06:25AM PDT, ID: 19194783

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About this solution

Zones: Microsoft Visual Basic.Net, Visual Basic Programming
Tags: null, type, conversion
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Solution Provided By: JuanCarniglia
Participating Experts: 3
Solution Grade: A
 
 
[+][-]06.01.2007 at 06:40AM PDT, ID: 19194878

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[+][-]06.01.2007 at 06:47AM PDT, ID: 19194924

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[+][-]06.01.2007 at 06:47AM PDT, ID: 19194933

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[+][-]06.01.2007 at 06:59AM PDT, ID: 19195013

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