# SQL Operators

The operators are symbols (and keywords) that are used to perform operations with values.

These operators are used with SQL clauses such as: `SELECT`, `WHERE`, `ON` etc.

The operators in SQL can be categorized as:

• Arithmetic operators
• Comparison operators
• Logical operators

## SQL Arithmetic Operators

Arithmetic operators perform simple arithmetic operations such as addition, subtraction, multiplication etc.

Operator Description
`+` Addition
`-` Subtraction
`*` Multiplication
`/` Divide
`%` Modulo (Remainder)

``````-- returns new column named total_amount which is
-- 100 added to the amount field
SELECT item, amount, amount+100 AS total_amount
FROM Orders;``````

### Subtraction Operator

``````-- returns new column named offer_price which is
-- 20 subtracted to the amount field
SELECT item, amount, amount-20 AS offer_price
FROM Orders;``````

### Multiplication Operator

``````-- returns new column named total_amount  which is
-- 4 multiplied to the amount field
SELECT item, amount, amount*4 AS total_amount
FROM Orders;``````

### Division Operator

``````-- returns new column named half_amount which is
-- divided by 2 to the amount field
SELECT item, amount, amount/2 AS half_amount
FROM Orders;``````

### Modulo (Remainder) Operator

``````-- returns 1 which is remainder
SELECT 10 % 3 AS result;``````

## Comparison Operators

We can compare two values using comparison operators in SQL. These operators return either `1` (means true) or `0` (means false).

Operator Description
`=` Equal to
`<` Less than
`>` Greater than
`<=` Less than or equal to
`>=` Greater than or equal to
`<>`, `!=` Not equal to

### Equal to Operator

``````-- returns records where customer_id is only 4
SELECT order_id, item, amount
FROM Orders
WHERE customer_id = 4;``````

### Less Than Operator

``````-- returns records where amount is less than 400 (exclusive)
SELECT order_id, item, amount
FROM Orders
WHERE amount < 400;``````

### Greater Than Operator

``````-- returns records where amount is greater than 400 (exclusive)
SELECT order_id, item, amount
FROM Orders
WHERE amount > 400;``````

### Less Than or Equal to Operator

``````-- returns records where amount is less than or equal to 400
SELECT order_id, item, amount
FROM Orders
WHERE amount <= 400;``````

### Greater Than or Equal to Operator

``````-- returns records where amount is greater than or equal to 400
SELECT order_id, item, amount
FROM Orders
WHERE amount >= 400;``````

### Not Equal to Operator

``````-- returns records where amount is not equal to 400
SELECT order_id, item, amount
FROM Orders
WHERE amount != 400;``````

Instead of `!=`, we can also use the `<>` symbol for not equal operations.

## Logical Operators

We can use logical operators to compare multiple SQL commands. These operators return either `1` (means true) or `0` (means false).

Logical operators available in SQL are,