Functions:
==========
Multi row functions:
====================
=> We can define on the entire table (on all columns of the table) at a time
and we can get a single value as return type.
=> The multi-row functions:
	1) max()
	2) min()
	3) sum()
	4) avg()
	5) count()

1) max():
---------
=> can return the maximum value from the group/collection.
Syntax:
	max(group/column-name)

Scenario:
---------
1) Creating the employee table
-------------------------------
create table ashokit_employees
(
	empId number(5),
	empFirstName varchar2(30),
	empLastName varchar2(30),
	designation varchar(40),
	department varchar2(40),
	salary decimal(10,2)
);

2) Insert the data into the table:
-----------------------------------
insert into ashokit_employees values(&empId, &empFirstName, &empLastName, &designation, &department, &salary);

3) commit the data:
-------------------
commit;

4) Find the maximum employee Id from the given table
=====================================================
Query:
	select max(empId) from ashokit_employees;

5) Find the maximum employee First name:
========================================
Query:
	select max(empFirstName) from ashokit_employees;

here:
	the maximum can be identified by the ASCII.

6) Find the maximum salary:
============================
Query:
	select max(salary) from ashokit_employees;


min():
------
syntax:
	min(collection/column)

sum():
------
Q: Write a SQL query to find the total estimations of employer for every month based on the given table?
Syntax:
	sum(column)

select sum(salary) from ashokit_employees;

avg():
------
=> to find the average of the given record, we can use avg().
Syntax:
	avg(record)

Q: Write a SQL a query to find the average salary of the ashokit_employees table?

select avg(salary) as AverageSalary from ashokit_employees;

Assignment:
-----------
1) Write a SQL query to find the minimum of employee last name.
2) Write a SQL query to find the minimum of employee department and designation.
3) Write a SQL query to find the total estimations of employer for the year according to the above table.

Note:
-----
avg() may return a value in floating-point format.
Ex: 1 + 2 + 3 + 4 + 5 + 6 / 6 ==> 3.5
=> to rounding-off or approximate the result of the avg(), we can use ceil()
Syntax:
	ceil(avg)

count():
--------
=> to count the capacity of any particular column, we can use below syntax:
	count(specific-column)
=> to count the capacity of whole table,
	count(*)

Ex:
select count(empId) from ashokit_employees;
select count(*) from ashokit_employees;