IBdataset1.Close;
IBdataset1.modifySQL.CLEAR;
IBdataset1.modifySQL.Text:= 'update PRESUPUESTO set monto='+quotedstr(form2.sedit1.Text)+
'WHERE EMPRESA ='+QUOTEDSTR(EMPRESA)+
'AND PERIODO >=' +encodedate(calendar1.year, calendar1.month, 1)+
'AND PERIODO <=' +encodedate(calendar1.Year, calendar1.Month,DaysInAMonth(calendar1.year, calendar1.month));
ibdataset1.ExecSQL;