![]() We will use the employees table in the sample database for demonstration purposes: SQL COUNT(*) examples Let’s take some examples to see how the COUNT function works. It counts duplicate rows and rows that contain null values. The COUNT(*) function returns the number of rows in a table in a query. The expression is a column of a table where you want to count the value.Īnother form of the COUNT function that accepts an asterisk (*) as the argument is as follows: COUNT(*) Code language: SQL (Structured Query Language) ( sql ).For example, the COUNT function returns 4 if you apply it to the group (1, 2, 3, 3, 4, 4). The DISTINCT keyword counts only unique values. ![]() By default, the COUNT function uses the ALL keyword whether you specify it or not. For example, if you have a group (1, 2, 3, 3, 4, 4) and apply the COUNT function, the result is 6. ![]() The ALL keyword will include the duplicate values in the result.The result of the COUNT function depends on the argument that you pass to it. The following illustrates the syntax of the SQL COUNT function: COUNT( expression) Code language: SQL (Structured Query Language) ( sql ) You can use the COUNT function in the SELECT statement to get the number of employees, the number of employees in each department, the number of employees who hold a specific job, etc. The SQL COUNT function is an aggregate function that returns the number of rows returned by a query. Summary: in this tutorial, you will learn how to use the SQL COUNT function to get the number of items in a group.
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