SQL over partition -avoid repeated statement in for every column
In standard SQL, you have a clause  where you can name the Partitioning option,but it is currently not supported by any RDBMS .You can see the connect item raised by Itzik Ben-Gan and vote for it

If implemented the Clause would look like this..

     SELECT empid, qty,
     SUM(qty) OVER W1 AS run_sum_qty,
     AVG(qty) OVER W1 AS run_avg_qty,
     FROM Sales.EmpOrders
    WINDOW W1 AS ( PARTITION BY empid
     ORDER BY ordermonth
     ROWS BETWEEN UNBOUNDED PRECEDING
     AND CURRENT ROW );