Group Functions

GROUP FUNCTIONS

a)    Sum
b)    Avg
c)    Max
d)    Min
e)    Count

Group functions will be applied on all the rows but produces single output.

a) SUM

  This will give the sum of the values of the specified column.

     Syntax: sum (column)

     Ex:   SQL> select sum(sal) from emp;

  SUM(SAL)
   ----------
     38600

b) AVG

     This will give the average of the values of the specified column.

     Syntax: avg (column)

     Ex:     SQL> select avg(sal) from emp;

   AVG(SAL)
   ---------------
   2757.14286

c) MAX

     This will give the maximum of the values of the specified column.

     Syntax: max (column)

     Ex:   SQL> select max(sal) from emp;

    MAX(SAL)
   ----------
     5000

d) MIN

     This will give the minimum of the values of the specified column.

     Syntax: min (column)

     Ex:    SQL> select min(sal) from emp;

   MIN(SAL)
   ----------
     500

e) COUNT

     This will give the count of the values of the specified column.

     Syntax: count (column)

     Ex:    SQL> select count(sal),count(*) from emp;

COUNT(SAL)               COUNT(*)
--------------         ------------
        14                   14