MySQL avg()

The AVG() function in MySQL is an aggregate function used to calculate the average (arithmetic mean) of values in a numeric column. It is commonly used to generate summary statistics about a dataset. The basic syntax of the AVG() function is as follows:

AVG(expression)

• expression: This should be a numeric column or a numeric expression from which you want to calculate the average.

Here are some common ways to use the AVG() function:

1. Calculate the Average of Values in a Column:
   To calculate the average of all values in a numeric column, use AVG(column_name).

   SELECT AVG(score) FROM test_scores;

2. Calculate the Average of Values Based on a Condition:
   You can calculate the average of values that meet specific conditions by using the AVG() function with a WHERE clause.

   SELECT AVG(price) FROM products WHERE category = 'Electronics';

3. Calculate the Average of Distinct Values in a Column:
   If you want to calculate the average of distinct (unique) values in a numeric column, you can use the AVG(DISTINCT column_name) syntax.

   SELECT AVG(DISTINCT temperature) FROM weather_data;

4. Calculate the Average of Values Grouped by a Column:
   When you want to calculate the average of values for each group within a dataset, you can use the GROUP BY clause with the AVG() function.

   SELECT department, AVG(salary) FROM employees GROUP BY department;

The AVG() function returns a numeric result, representing the arithmetic mean of the values in the specified column. It is a useful tool for calculating the average value of a dataset, such as average test scores, average prices, or average salaries in a specific department.