Question

Ok, I’m doing a self query to suppress duplicates for a view. The code I’m using is:

    USE BILLING

    SELECT Provider_Code,
           Provider_LName,
           Provider_Fname,
           Provider_Title,
           AGENCY_LOCATION_NAME_LINE_1,
           CostCenter_AbbrName
    FROM   dbo.ServiceProfiler prov1
           INNER JOIN
           dbo.ServiceProfiler prov2
           ON prov1.Provider_Code = prov2.Provider_Code
    WHERE  0 = (SELECT COUNT(s1.Provider_Code)
                FROM   prov1
                WHERE  prov2.Provider_Code = prov1.Provider_Code
                       AND prov2.Provider_Code < prov1.Provider_Code);

When executing the query on SQL Server 2005 I get the message:

Msg 208, Level 16, State 1, Line 3
Invalid object name ‘prov1’.

I cannot for the life of me understand why the alias names are invalid. I think I found a similar question here. But it’s very generic and doesn’t show a full ‘real’ query using the aliases.

Answer 1

I’d do something more like this:

SELECT Provider_Code,
           Provider_LName,
           Provider_Fname,
           Provider_Title,
           AGENCY_LOCATION_NAME_LINE_1,
           CostCenter_AbbrName
FROM   dbo.ServiceProfiler prov,
     (SELECT Provider_Code,count(*) Count from dbo.ServiceProfiler group by Provider_Code HAVING count(*)=0) q
WHERE prov.Provider_Code = q.Provider_Code

You could also do a straight up sub-select, I’d imagine. I think joining on a subquery is easier to understand, but that’s me.