Re: Procedure that select different number of columns

[Zawisza Czarny]

> If you fetch only 300 rows, almost any solution (brute force or otherwise) will have "good enough" performance. So, it might be best to focus on simplicity of the implementation, not on performance.
You are absolutely right! But because this is my first app that uses MySQL I just wanted to learn a good practise in designing a database...

And how about writing a query that returns to application env table? (cut only to item that interests me of course) I still will be able to filter items in DB, and I will not have to write a stored procedure to make a pivot table, and I don't need to use JSON in my app,