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How do I check for NULL DB Records in this C# Code?

The following code is a static function used to calculate the NEXT ID created by the database. The code needs to perform a basic initial check to ensure that if there are no records in the table it can take the appropriate action. eg Make the First row 1. eg Try/Catch or IF/Else.

public static int SiteIDMax()
{                                                    
int SiteID;
SiteID = Convert.ToInt32(ew_ExecuteScalar("SELECT max(SiteID) FROM DMPDB.DMP_Sites"))+ 1;  
//HttpContext.Current.Response.Write(Convert.ToInt32(SiteID));
return SiteID;
}

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kaufmed

Try:

object result = ew_ExecuteScalar("SELECT max(SiteID) FROM DMPDB.DMP_Sites");

if (result != DBNull.Value)
{
    SiteID = Convert.ToInt32(result);
}

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XGIS

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joriszwaenepoel

For a SQL Server database, you can modify the query so it never returns NULL, like this:

SELECT ISNULL(max(SiteID),1) FROM DMPDB.DMP_Sites

Other database servers have similar functions. I think for Oracle the function name is NVL.

XGIS

ASKER

Hello Kaufmed.. thankyou for your time and logic... unfortunately it was a little bit more tricky working inside another application's implementation of C#. The solution resolves the null issue and correctly assigns folders based on subsequent dependent code. I am sure this solution could be tidier..but "works" is more important than "tidy" for me.

XGIS

ASKER

Hello joriszwaenepoel... good call.. I have used this approach before and it is good based on the fact it eliminates messy codes.. I will give it a test, although my problem has been resolved. Cheers