The target is to multiply the value of the field EEA (table Immesso) for the field N_VALORE_1(table PrezziMGP) if the value of the field ORA (table Immesso) is 1, for the field N_VALORE_1(table PrezziMGP) if the value of the field ORA (table Immesso) is 2, etc.
The mail problem is that the table Immesso has 24 rows for each day (field DT_DATA), instead the table PrezziMGP has only 1 row foe every day (field DT_DATA).
So, when I linked the two tables, the result is that I see valorized only the rows with field ORA equal to 1.