Data Modifications in SQL/Oracle

SQL AND & OR Operators

· The AND operator uses to satisfy two conditions. That is it returns true only if two conditions are satisfied.

· The OR operator return true only if one of the conditions are satisfied.

Select * from employee_dtl where department_id=1 and designation_id=3

Emp_Id	Emp_Name	Department_id	Join_dt	Designation
10254	Meera	1	09/04/2006	3

Select * from employee_dtl where department_id=1 or designation_id=3

Emp_Id	Emp_Name	Department_id	Join_dt	Designation
10001	Manu	1	06/06/2008	1
10254	Meera	1	09/04/2006	3

Select * from employee_dtl where department_id =1 and (designation_id=1 or designation_id=4)

Emp_Id	Emp_Name	Department_id	Join_dt	Designation
10001	Manu	1	06/06/2008	1

The ORDER BY Keyword

· Used to sort the result set by a specified column

· By default it sort in ascending order

· DESC is the keyword used to sort in descending order

SELECT column_name(s)
FROM table_name
ORDER BY column_name(s) ASC|DESC.

Select * from employee_dtl order by join_dt

Emp_Id	Emp_Name	Department_id	Join_dt	Designation
10254	Meera	1	09/04/2006	3
10001	Manu	1	06/06/2008	1
13654	Thilak	2	09/05/2009	4

Select * from employee_dtl order by emp_code desc

Emp_Id	Emp_Name	Department_id	Join_dt	Designation
13654	Thilak	2	09/05/2009	4
10254	Meera	1	09/04/2006	3
10001	Manu	1	06/06/2008	1