How to get absolute value using ABS function in MySQL
How to use the ABS function in MySQL to get the absolute value
Absolute value is a commonly used concept in mathematics. It represents the distance of a number from zero. In programming, sometimes we need to take the absolute value of a certain number in order to make some logical judgments or calculations. In MySQL, we can use the ABS function to get the absolute value. This article will explain how to use the ABS function in MySQL and provide some code examples.
1. Overview of ABS function
The ABS function is a mathematical function in MySQL, which is used to return the absolute value of a number. The syntax is as follows:
ABS(x)
Among them, x is the value that needs to be absolute. The return value type of the ABS function is the same as the type of x.
2. Examples of using the ABS function
Let’s look at some examples of using the ABS function.
- Get the absolute value of an integer
SELECT ABS(-10); --The result is 10
In this example, we use the ABS function to get The absolute value of a negative number -10. The return result is 10, which means that the absolute value of -10 is 10.
- Get the absolute value of the decimal
SELECT ABS(-3.14); -- The result is 3.14
In this example, we use the ABS function to get The absolute value of decimal -3.14. The returned result is 3.14, which means the absolute value of -3.14 is 3.14.
- Get the absolute value of the field value
Suppose we have a table students, which has a field score used to store students' scores. We want to query students whose absolute value of score is greater than 90. You can use the ABS function to achieve this:
SELECT * FROM students WHERE ABS(score) > 90;
In this example, we use the ABS function to take the absolute value of the field score and compare it with 90 Compare. If the absolute value is greater than 90, it means that the score is greater than 90 or less than -90, that is, the student meets the requirements.
- Get the absolute value of the calculated field
Suppose we have a table orders, which has two fields price and quantity used to store the unit price and quantity of the order. We want to query the orders whose absolute value of the total price is greater than 100. You can use the ABS function to achieve this:
SELECT , ABS(price quantity) AS total_price FROM orders WHERE ABS(price * quantity) > 100;
In this example , we use the ABS function to take the absolute value of the calculated field price * quantity and compare it with 100. If the absolute value is greater than 100, it means that the total order price is greater than 100 or less than -100, which is an order that meets the requirements. At the same time, we use the AS keyword to give the calculation result an alias total_price to facilitate subsequent use.
Summary
Through the above examples, we can see that the use of the ABS function is relatively simple. In practical applications, we can flexibly use ABS functions according to specific needs. Whether it is to take the absolute value of an integer or decimal, or to take the absolute value of a field or calculated field, the ABS function can help us achieve it easily.
I hope this article will help you understand how to use the ABS function to get the absolute value in MySQL. If you have any questions, please leave a message to communicate.
The above is the detailed content of How to get absolute value using ABS function in MySQL. For more information, please follow other related articles on the PHP Chinese website!

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