How to Check Database Size in MySQL

Running a Query

1. Connect to a MySQL server. There are a number of apps you can use to connect to a MySQL database, including MySQL Workbench. You can also query a MySQL database in the command line in Windows, or terminal on Mac. Once MySQL is installed on your computer you'll need to navigate to the MySQL directory in the Windows command line and type mysql -u root -p. Then enter the password for your database.

2. Type SELECT table_schema "DB Name", as the first line of your query. This is the select command to query run a query on the database.

3. Type SUM(data length + table length) 'Size in bytes', as the second line. This command will display the size of each table in bytes.

4. Type ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) 'Size in MiB' as the next line. This displays a rounded number of the size in megabytes.

   1. To display a rounded number in kilobytes, type ROUND(SUM(data_length + index_length) / 1024, 2) 'Size in KiB' instead.^{[3] X Research source}

5. Type FROM information_schema.tables as the last line. This command specifies which database tables to query.

6. Type GROUP BY table_schema; and execute the query. This will display the size of your databases. You can also type {[kbd|WHERE table_schema = 'database name';}} to check the size of a specific database. Type the actual name of the database in place of "database name". Your query should look something like this:

    SELECT table_schema "DB Name" SUM(data length + table length) 'Size in bytes', ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) 'Size in MiB' FROM information_schema.tables GROUP BY table_schema;