SELECT first_name, country

FROM Customers

WHERE country IN ('USA', 'UK');

Used alongside a WHERE clause as a shorthand for multiple OR conditions.

So instead of:

SELECT * FROM users

WHERE country = 'USA' OR country = 'United Kingdom' OR

country = 'Russia' OR country = 'Australia';

You can use:

SELECT * FROM users

WHERE country IN ('USA', 'United Kingdom', 'Russia',

'Australia');

=   Checks if the values of two operands are equal or not, if yes then condition becomes true.  (a = b) is not true.

!=  Checks if the values of two operands are equal or not, if values are not equal then condition becomes true. (a != b) is true.

<>  Checks if the values of two operands are equal or not, if values are not equal then condition becomes true. (a <> b) is true.

>   Checks if the value of left operand is greater than the value of right operand, if yes then condition becomes true. (a > b) is not true.

<   Checks if the value of left operand is less than the value of right operand, if yes then condition becomes true.    (a < b) is true.

>=  Checks if the value of left operand is greater than or equal to the value of right operand, if yes then condition becomes true. (a >= b) is not true.

<=  Checks if the value of left operand is less than or equal to the value of right operand, if yes then condition becomes true.    (a <= b) is true.

!<  Checks if the value of left operand is not less than the value of right operand, if yes then condition becomes true.    (a !< b) is false.

!>  Checks if the value of left operand is not greater than the value of right operand, if yes then condition becomes true. (a !> b) is true.

-- IN is a shortcut of OR for a list of values that exist in same column

​

SELECT col1, col2

FROM table_name

WHERE col2 = 'A' AND (col1 = 1920 OR col1 = 1930 OR col1 = 1940);

​

-- Now since col1 has multiple values with OR, we can replace these OR with IN

SELECT col1, col2

FROM table_name

WHERE col2 = 'A' AND col1 IN (1920, 1930, 1940);

(IN) operator in sql like "OR" operator

For example: 

Select * From employees

Where department_id "IN" (60,90); 

​

SELECT EmpId FROM EmployeeDetails

UNION 

SELECT EmpId FROM EmployeeSalary;

​

SELECT EmpId,

Salary+Variable as TotalSalary 

FROM EmployeeSalary;

​

SELECT column1, column2, ...

FROM table_name

WHERE column_name IN (value1, value2, ...);

(IN) operator in sql like "OR" operator

For example: 

Select * From employees

Where department_id "IN" (60,90); 

​

SELECT FullName

FROM EmployeeDetails

WHERE FullName LIKE ‘__hn%’;

​