SQL FUNCTIONS FOR PERFORM DIFFERENT TASKS

1. SQL Functions

2. FUNCTION?
Stored piece of program that manipulates submitted
Data and return some value.

3. TYPES OF FUNCTIONS
o String Functions
o Numeric Functions
o Group Functions
o Date andTime Functions

4. GROUP FUNCTIONS
Group functions are mathematical functions to operate on sets of rows to give one
result per set.

5. TYPES OF GROUP FUNCTIONS
o AVG
o COUNT
o MAX
o MIN
o SUM
o TRUNCATE

6. 1.AVG:
RETURNS THE AVERAGE VALUE OF AN EXPRESSION
QUERY:
SQL> SELECT AVG(SAL) FROM EMPLOYEE;
2.COUNT:
Returns the number of records returned by a select query
Query:
SQL> select count (USERID) from employee;

7. 3.MAX:
RETURNS THE MAXIMUM VALUE IN A SET OF VALUES
QUERY:
SQL> SELECT MAX(SAL) FROM EMPLOYEE;
4.MIN:
Returns the minimum value in a set of values
Query:
SQL> select min(sal) from employee;

8. 5.SUM:
CALCULATES THE SUM OF A SET OF VALUES
QUERY:
SQL> SELECT SUM(SAL) FROM EMPLOYEE;
6.TRUNCATE:
Truncate a value to a specified limit
Query:
SQL> select truncate(avg(sal),2) from employee;