Which MySQL command shows table sizes and what column indicates the largest tables?

Other Questions MySQL
1

I need to find out which tables are taking up the most space in my MySQL database. I found this command that seems to work:

SELECT table_name, data_length, index_length 
FROM information_schema.tables 
WHERE table_schema = 'your_database_name';

The output shows several columns with different numbers and I’m not sure which one tells me the actual table size. Should I be looking at data_length or index_length? Or do I need to add them together? I want to identify the tables that are using the most disk space so I can optimize my database.

2

yup! just sum up data_length and index_length for the full size. data_length is just the raw data, while index_length takes up space too. add ORDER BY (data_length + index_length) DESC to see the largest tables first!

3

The command you’ve found is effective for assessing table sizes. To determine the total space usage, you should consider both data_length and index_length as they together represent the complete size of each table. Additionally, if you want a more user-friendly output, I recommend converting the bytes into megabytes for easier interpretation. For instance, you could use: SELECT table_name, ROUND((data_length + index_length) / 1024 / 1024, 2) AS 'Size in MB' FROM information_schema.tables WHERE table_schema = 'your_database_name' ORDER BY (data_length + index_length) DESC;. This way, the largest tables pop up first and the size is more comprehensible.