Query error with ambiguous column name in SQL

Question

I get an Ambiguous column name error with this query (InvoiceID). I can\'t figure out why. They all seem to be joined correctly so why doesn\'t the management studio know to

Answer 1

I think you have ambiguity only in InvoiceID. Other fields seem distinct. So try This

I just replace InvoiceID with Invoices.InvoiceID

   SELECT 
        VendorName, Invoices.InvoiceID, InvoiceSequence, InvoiceLineItemAmount
    FROM Vendors 
    JOIN Invoices ON (Vendors.VendorID = Invoices.VendorID)
    JOIN InvoiceLineItems ON (Invoices.InvoiceID = InvoiceLineItems.InvoiceID)
    WHERE  
        Invoices.InvoiceID IN
            (SELECT InvoiceSequence 
             FROM InvoiceLineItems
             WHERE InvoiceSequence > 1)
    ORDER BY 
        VendorName, Invoices.InvoiceID, InvoiceSequence, InvoiceLineItemAmount

You can use tablename.columnnae for all columns (in selection,where,group by and order by) without using any alias. However you can use an alias as guided by other answers