![]() ![]() That value is NULL, and MySQL count column values only works when those values are not NULLs. The command returned only 3 entities because the 4th one does not have any value in the description column. Suppose we are going to count the number of movies that have a description using the SELECT COUNT option: SELECT COUNT(description) Assume that our sakila database includes a table called film with such columns: film_idĪ magical realism drama film written and directed by Frank Darabont and based on Stephen King’s 1996 novel of the same name.Ī black comedy crime film written and directed by Quentin Tarantino, who conceived it with Roger Avary.Ī comedy-drama film directed by Robert Zemeckis and written by Eric Roth. However, unlike COUNT(*), COUNT(expression) does not count NULL values at all – such rows are ignored. The expression plays the same role as the WHERE clause above – it defines the condition for the data to be returned. COUNT(expression)ĬOUNT(expression) is the most common method we use to count records. To execute the query, paste it into the SQL window and either click, or press F5. The command looks as follows: SELECT COUNT(*) We are going to find out how many new movies were released in 2012. In practice, we work with three types of this function:ĬOUNT(*) is a variant counting all the results returned by SELECT, including NULLs and duplicates.Īs an example, let’s take the sakila database that contains the film table. An example of using the COUNT function COUNT That is exactly what we are going to do further in this article. Here, you can type in and execute any query. Once the connection is up, click New SQL.ĥ. ![]() If everything is set correctly, you will see the Successfully connected message. Fill in the corresponding database connection properties and click Test Connection.ģ. Click New Connection in the Database menu.Ģ. To begin your dbForge Studio journey, you need to create a connection:ġ. Its rich functionality is delivered under an intuitive interface. It is a full-fledged MySQL GUI that helps create and execute queries, develop and debug stored routines, automate database object management, compare and synchronize databases, analyze table data, and much more. In this article, we are going to demonstrate how to use different manifestations of the COUNT function in dbForge Studio for MySQL.
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