MySQL将一个表绑定到多个表的最佳方法是什么？

Question

I'm not too sure how to word my question, but here it is.

Let's say I have multiple tables, dogs , cats , and birds . Each of them have uploads related to them. Each can have many, so I figured it would be best to be on its own table.

Which is a better approach?

1. a single uploads table with for taking the table (say dogs ), and for_id referencing the id of that column
2. a single uploads table with a columns dogs_id , cats_id , birds_id , with one of them filled with the relative id
3. multiple tables, named uploads_dogs , uploads_cats and uploads_birds

Or maybe there is a better appraoch?

Thank you!

Answer 1

You could use a single uploads table with a type id (birds = 1, cats = 2, etc.) and an object id column containing the ID of the cat/bird/dog. So when you want to find all uploads for a given cat:

    SELECT * FROM uploads WHERE typeId = 2 AND objectId = [catId]