AND & OR

The SQL AND and OR operators are used to combine multiple conditions to narrow data in an SQL statement. These two operators are called conjunctive operators. These operators provide a means to make multiple comparisons with different operators in the same SQL statement.

The basic syntax for the WHERE clause when used in a SELECT statement is as follows.:

WHERE condition1 AND condition2...OR condition_n;

Employee
Emp_id	Name	Surname	Salary	Dept_id
1	Rajesh	Khanna	45000	2
2	Sneha	Gupta	55000	4
3	Sandeep	Nehte	95000	1
4	Kirti	Patil	25000	3
5	Nilesh	Jadhav	45000	3
6	Dipesh	Das	35000	5
7	Kailash	Rane	62000	1
8	Kavita	Deshpande	48000	3
9	Sanjay	Datt	50000	2
10	Shruti	Hasan	78000	1
11	Sandeep	Deshmukh	52000	3

USING AND CONDITION:

USING AND CONDITION: SQL AND clause are used when you want to specify more than one condition in your SQL WHERE clause, and at the same time, you want all conditions to be true. 

SELECT * FROM Employee WHERE Dept_id = '1' AND Salary > 50000;

After Execution:

Emp_id	Name	Surname	Salary	Dept_id
3	Sandeep	Nehte	95000	1
7	Kailash	Rane	62000	1
10	Shruti	Hasan	78000	1

USING OR CONDITION:

You can combine N number of conditions using OR operator.

Basic Syntex:

SELECT column1, column2, columnN FROM table_name WHERE [condition1] OR[condition2]...OR [conditionN]

SQL Syntex:

SELECT * FROM Employee WHERE Name = 'Sandeep' OR Name = 'Kailash' ;

After Execution:

Emp_id	Name	Surname	Salary	Dept_id
3	Sandeep	Nehte	95000	1
7	Kailash	Rane	62000	1
11	Sandeep	Deshmukh	52000	3

We can also use more then one OR Clause in SQL Query:

SELECT * FROM Employee WHERE Name = 'Sandeep' OR Name = 'Kailash' OR Dept_id='2';

After Execution:

Emp_id	Name	Surname	Salary	Dept_id
3	Sandeep	Nehte	95000	1
7	Kailash	Rane	62000	1
9	Sanjay	Datt	48000	2
11	Sandeep	Deshmukh	52000	3

COMBINING AND & OR CONDITIONS

SELECT * FROM Employee WHERE (Dept_id = '3' AND Surname = 'Gupta') OR (Salary>50000);

After Execution:

Emp_id	Name	Surname	Salary	Dept_id
2	Sneha	Gupta	55000	4
3	Sandeep	Nehte	95000	1
7	Kailash	Rane	62000	1
10	Shruti	Hasan	78000	1
11	Sandeep	Deshmukh	52000	3