How can I write a model using only django for a tree like menu with categories, sub categories and sub-sub categories amd will require just one query to enter each menu?
Are you sure that there’s only going to be three levels? Do you know how many entries there are going to be? Are those entries effectively static? (Are they going to change over time or usually expected to remain the same?)
Also, how are you going to use this data for your menu? Are you going to pre-render the entire menu, or are you expecting the menu to be sufficiently dynamic such that you need to request different submenus?
In general terms, if you’re limited to three levels, I wouldn’t worry about getting too fancy with the data structure. Pretty much anything will work out for you given that you’re likely to spend more time organizing and rendering the data within your template than what the query will consume.
I used three levels as example. But I’m expecting possible more levels on some or even less on others
Fewer levels isn’t a problem. However, allowing for a larger number of levels does materially change the considerations involved.
In the general case, I suggest you see this post, and the links referenced from it: Some modelling advice - #12 by KenWhitesell
There are other posts here in the forum discussing hierarchical storage of data - the key item to remember is that the different algorithms optimize different operations. There’s no one-size-fits-all solution for this - it’s one of those situations where the appropriate answer is extremely context-sensitive.
What about answers to the rest of the questions? Depending upon your answers, there may be other simplifications that can be performed.
Thanks, I would just like to render everything and when a user clicks on each item, they go to the url specified on it