【MySQL】Aggregate Functions｜MAX() MIN() SUM() AVG() COUNT()

Aggregate functions are indispensable when analyzing data in MySQL. These functions perform specific calculations on a dataset, providing valuable information. In this section, we will explain the types of aggregate functions commonly used and how to use them.

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MySQLデータの検索【SELECT文・WHERE句・演算子】

EnglishMySQLにおけるデータ検索は、データベース管理の基本であり、その効率的な運用には欠かせません。この記事では、SELECT文の基本から始め、WHERE句で使用されるAND、OR、NOTといった重要な演算子...

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Using the MAX Function

The MAX function returns the highest value in a specified column. For example, to find the highest score in the entry_exam column of the students table, you would use the following query:

SELECT
MAX(entry_exam)
FROM students;

Using the MIN Function

The MIN function returns the smallest value in a column. To find the lowest score in the students table, you would use this query:

SELECT
MIN(entry_exam)
FROM students;

Calculating Total Value with the SUM Function

The SUM function calculates the total of all values in a column. To find the total of scores in the entry_exam column, you would use:

SELECT
SUM(entry_exam)
FROM students;

Calculating Average Value with the AVG Function

The AVG function returns the average value of a column. To find the average score in the entry_exam column of the students table, you can use this query:

SELECT
AVG(entry_exam)
FROM students;

Counting Data with the COUNT Function

The COUNT function counts the number of data entries in a column. For example, to find the number of records that have data in the entry_exam column, you would use:

SELECT
COUNT(entry_exam)
FROM students;

Summary

Aggregate functions are a powerful tool in data analysis. By mastering these functions, you can gain valuable insights from the information within your database. However, when using aggregate functions, it’s important to understand the nature of your data and the purpose of your analysis.