SQL duplicate management

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It turns out that I have to make a query in which I get returned several duplicate records, except for a field that is counters.

The question in itself is that I need to collect the record with the highest value of counters. Right now the sentence is as follows 

SELECT * FROM Bares B inner JOIN Contadores C on B.idProd = C.idLocal where B.EmpresaOperadora='B'

What returns me

Of those 3 records, I should draw first since it is not repeated and the last one since it is the one with the highest value of countersEntradas. I understand that it must be an easy thing, but I am not very focused on this topic and what I have tried has not been a good result. Greetings

    
asked by Nuxk 07.05.2018 в 12:47
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1 answer

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I think the key is in the MAX function, it's an aggregate function and for example combined with GROUP BY I think I can help you with this query.

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On the other hand, for you to have an example that can help you, I would touch up your query in this way: 

SELECT idProd, nombreBar, Maquina, MAX(contadoresEntradasAnteriores) FROM Bares B inner JOIN Contadores C on B.idProd = C.idLocal where B.EmpresaOperadora='B
GROUP BY idProd, nombreBAR, Maquina

I hope you can use at least guidance

    
answered by 07.05.2018 в 13:04
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