Some Kind Of Calculation Is Needed For This Query?

Hi,

I have a query which gives me the following results:

lLedgerCode sGLCode bDebit TotalSum sGLDesc
61 6843000701 0 600ALPS Holding
33 8345000701 0 1116ALPS Premium Due
56 1000000701 0 1116Regular Premium Income
63 6836000701 1 516ALPS Group Holding
61 6843000701 1 600ALPS Holding
30 6842000701 1 600ALPS Policy Clearing
33 8345000701 1 1116ALPS Premium Due


The Column bDebit has either value '0' or value '1' in it ('0' being debit - positive amount, and '1' - credit, negative amount).

I would like it to show the net amount for each account. Therefore in plain English I would like to take all GLCodes that are the same (eg 6843000701) and sum all amounts that have debit value of '0' and subtract all amounts that have debit value '1'. Therefore I would only see '6843000701' code once, and the amount would be '0' becase 600 - 600 = 0.

The current query is:
SELECT dbo.tbGLTransactions.lLedgerCode, dbo.tbGLTransactions.sGLCode, dbo.tbGLTransactions.bDebit, SUM(curAmount)As TotalSum, dbo.tbLedgerCode.sGLDesc
FROM dbo.tbGLTransactions
INNER JOIN dbo.tbLedgerCode
on dbo.tbGLTransactions.lLedgerCode = dbo.tbLedgerCode.lLedgerCode
WHERE dbo.tbGLTransactions.lGLExtractRun = '452'
Group By dbo.tbGLTransactions.lLedgerCode, dbo.tbGLTransactions.sGLCode, dbo.tbGLTransactions.bDebit, dbo.tbLedgerCode.sGLDesc
Order By dbo.tbGLTransactions.bDebit, dbo.tbLedgerCode.sGLDesc



Is someone able to help me as to how i need to modify this query to get the desired result?

Thanks!