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Databases

Ranvir Sahota
Ranvir Sahota
9,844 Points

Column is specified but still ambiguous

I have resolved the issue however I fail to understand why the column was ambiguous. The problem with the code was I repeating the table that I was using for INNER JOIN in the FROM section. But why should this cause ModelName to be ambiguous.

SELECT Model.ModelName AS 'Model Name', Car.VIN, Car.StickerPrice AS 'Sticker Price' FROM Car, Model INNER JOIN Model ON Car.ModelID=Model.ModelID

1 Answer

Steven Parker
Steven Parker
229,645 Points

It becomes ambiguous when you have two of the same thing.

When you include the table the second time, you now have two columns with exactly the same name, so the database engine can't determine which one of the two you are asking for in your SELECT clause.

To resolve such an ambiguity, you would need to be able to distinguish the columns from each other. A table alias would be useful in such a case.

Ranvir Sahota
Ranvir Sahota
9,844 Points

Thanks for that and sorry for not making question clear the first time