Eloquent/Laravel: Nested lazy eager loading, but return multiple model's relations

Question

Apologies if the title does not make much sense, but here's what I've got and what I'd like to achieve.

There's a restaurant's menu, which is structured like this:

Restaurant
|- category 1
   |- subcategory 1
   |- subcategory 2
      |- item 1
         * price levels:
         |- price level 1
         |- price level 2
         * modifiers groups:
         |- group 1
            |- modifier 1
            |- modifier 2

The goal is to write the most efficient way (in terms of database queries) to get the entire menu (served as JSON via API), but there's a catch: I need both price levels AND modifiers for each item.

The most efficient way that I came up with is:

Part 1: chain all the way up to item's modifiers (because they're more nested than price levels):

$this->restaurant->load('categories.subcategories.items.modifier_groups_enabled.modifiers_enabled');

Part 2: Before starting the loop through categories/subcategories/items, I "manually" get all price levels that belong to all items in a restaurant, then I put them into an array, grouped by item's id. Then, while looping through the menu, I just grab the $price_levels[$item->id] as an array of item's price levels.

With nothing cached, the entire request is complete in 7 queries, which is OK, but the 'dirty' way of preparing price levels is bothering me a bit :)

If I cut the nested eager loading up to items only, then get each item's price levels and modifiers ($item->load[...]), database queries pile up since each item runs its own ones to get price levels and modifier groups/modifiers.

So, the question is: Can $this->restaurant->load('...') be written in such a way that it also returns all items' price levels AND modifiers?

Aken Roberts · Accepted Answer · 2015-12-04 18:27:11Z

1

So, the question is: Can $this->restaurant->load('...') be written in such a way that it also returns all items' price levels AND modifiers?

Of course, just specify price levels the same way as modifier groups:

$this->restaurant->load(
    'categories.subcategories.items.modifier_groups_enabled.modifiers_enabled',
    'categories.subcategories.items.price_levels'
);

answered Dec 4, 2015 at 18:27

Aken Roberts

13.5k3 gold badges38 silver badges42 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Oliver Maksimovic Over a year ago

Ouch, I've never thought about that (haven't seen a similar example either). Big thanks, it's a lot more elegant this way, and even slightly faster than what I've had.

Aken Roberts Over a year ago

The first example under Lazy Eager Loading shows the loading of two relationships. You're pretty much doing the same, you're just loading two relationships of a nested relationship, so your initial categories.subcategories.items will be the same for both.

Oliver Maksimovic Over a year ago

Yep, I just didn't think I'd work properly (or at all) with nested relationships and I didn't even try to see if it'd throw an error... just dismissed it as not possible (and tried many other crazy stuff instead). Need to work on abandoning that approach :)

Collectives™ on Stack Overflow

Eloquent/Laravel: Nested lazy eager loading, but return multiple model's relations

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related