MySQL Database Design Optimization

Question

(First off, sorry if this has been asked before, I searched for a while but its hard to find an older specific question sometimes)

I am currently working with an order management system (PHP, MySQL, HTML...) and I am considering some changes to the db schema for the next iteration.

I have tables such as Order, Purchase_Order, Inquiry, and a couple more that all have "notes", "files", and one or two more shared components. Right now they are all stored in their own respective tables (Order_Note, Purchase_Order_Note, Order_File, etc..). My question is will combining the "notes" into a single table be of any benefit?

Proposed:

table "Order" (Purchase_Order, etc..) stores all order-specific fields

table "Order_Note_Map" (PO_Note_Map, etc..) stores the ID of the order and ID of the related note

table "Notes" stores a notes details

Edit:

-the DB at the moment has less than 3,000 total "notes" spread across tables with that number increasing but not at a significant rate, roughly the same number of records for the other items I am asking about

-looking back I think a big caveat of the current system was with changing the components of a "note". instead of changing one table I have to make identical changes in multiple. Not a big deal if I can avoid a major DB change

Answer 1

This question would be clear if you can tell how much of records are you having in these tables or expecting. If they are high volume then I would suggest combining into one would help as you would not be joining tables to get data. Joining would be costly in large data set.

Answer 2

The short answer is no because you will only have a join less and it sounds like you will have to change a lot just to change this thing. If your database is "huge" it will be smart to put the notes into a single table but if your database won't be to big it won't change anything. It will only be a little faster.