Thank you so much. I tried this and work. Only I wanted ask you which way is the best.

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set HidePrefix='_' ;

[TABLE]:

LOAD

[id],

[idTiempo] AS [_TABLE.idTiempo], <-- This

[idProducto],

[idConcepto],

[idUnidad] AS _[TABLE.idUnidad], <-- Or this

[valor] AS [TABLE.valor];

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Thanks again.