new to laravel.
My use case:
Update multiple rows (say: resources table).
Create multiple users (users table).
Retrieve ids of created users
What I currently did:
First, Update the resources table whereIn('id', [1,2,3,4]). (Update eloquent)
Second, Get array of the updated resources (Another eloquent: Resource::whereIn('id', [1,2,3,4])->get()->toArray())
Bulk create a users. Refers to the resources collection above. (Another eloquent: User::create($resources))
Lastly, get the ids of the created users (Not resolved yet. But I might have to use another eloquent query)
All in all, there are 4 Eloquent queries, which I want to avoid, because this might have performance issue.
What I wanted to do is that, On first step(Update), I should be able to get a collection of models of the affected rows (But I can't find any reference on how to achieve this). And then use this collection to create the users, and get the users ids in one query with User::create() so that I will have 2 queries in total.
There is no need to invent performance problems that do not exist.
Update or Insert return only count of affected rows. Commands Select, Insert, Update performed separately. This is a SQL issue, not Laravel.
For single inserts (if you want add one row) you can use insertGetId method of a model.
For example,
$id = User::insertGetId([
'email' => 'john#example.com',
'name' => 'john'
]);
But you get only ID of record. You need to run select to get full data of the row.
To save multiple records with one query you can use
DB::table('table_name')->insert($data);
Since this won't be an eloquent method, you should pass all the columns including created_at and updated_at.
I don't know what is the method name for update.
Related
I found that laravel 'pluck' return an plain array and 'select' return an object. Can anyone explain it to me have any other different between two this?
thank you.
Pluck is a Laravel Collections method used to extract certain values from the collection. You might often want to extract certain data from the collection i.e Eloquent collection.
While Select is a normal selection of either multi or specific columns. They are
By using Pluck you only ask to return necessary fields, but with get you will pull all columns. Also select does the same & the difference here is between the returning result. Using pluck cause returning the final result as an array with pair of given arguments, but select return an array (or object) which every single child contain one row.
$name = DB::table('users')->where('name', 'John')->pluck('name');
Select
EX : DB::table('users')->select('id', 'name', 'email)
Select is a method sent to the database that Laravel will translate as
SELECT id, name, email FROM users
This will select the data of the columns you asked and nothing else. It allows you to be more efficient with your request by only asking the required data. Take the example above and image that the user is a Facebook user. It has a ton of data on it, plus relations to other tables. If you just want to display the name, email and a link to the user profile, doing this request!
For more info and knowing more about the expected response visit : https://laravel.com/docs/9.x/queries#select-statements
Pluck
EX:
$users = DB::table('users')->where('roles', '=', 'admin')
$emails = $users->pluck('email')
The Pluck method retrieves the values in a collection that you already got from the Database and that is now a Laravel Collection. This allows you to create an array of the plucked data, but will not improve the performance of your request, as in the Example above, the $users would hold all data of all the admin users.
Since it does not improve performance, what good is it then ?
The pluck would be useful for example to separate some datas in different variables depending on where. You might need the users data for some stuffs, but also want to display a quick list of all emails together.
For more info about the pluck method and understand how to create a keyed array from a second column, visit the docs here: https://laravel.com/docs/9.x/collections#method-pluck
Pluck function normally used to pull a single column from the collection or with 2 columns as key, value pairs, which is always be a single dimension array.
Select will return all of the columns you specified for an entity in a 2 dimensional array, like array of selected values in an array.
Note: Pluck function is a collection function which happens after the data is fetched. Select is a query builder function that builds query to perform in the database server.
Actually select is used inside DB queries, which can affect the performance by limiting the pulled columns. However, Pluck is Laravel Collection's method, so you can use pluck after you pull the data from DB.
I am making a multi-vendor ecommerce website using Laravel 7. I am trying to make an Order History page where in a single can user can view only his/her own orders. I am having a problem building the query on my OrderHistoryController. These are the codes on my controller:
$users = User::get();
$orders = Order::find($users);
return view('order-history', compact('orders'));
And I'm trying to loop $orders on my blade file. I have:
#foreach ($orders as $order)
<div>{{ $order->id}}</div>
<div>{{ $order->grand_total}}</div>
#endforeach
I am trying to pass the order id and order grand total to my view. I don't get any error however it shows a different order details from a different customer. How do I do this?
You should use MySQL (or any other database you are using) table relationships and foreign keys.
So, your orders table, should have columns id, user_id, date, and so on. The important thing is user_id column. You want to make that column a foreign key. That basically means that user_id will hold an id value from another table, in this case user. See how to make foreign key columns in laravel migrations here.
Next up is to use Laravel's built in model relationships. You can read more about them here. Basically, in your orders model you want to have a function user which returns $this->belongsTo(App\Models\User::class) and in your user model you want to have a function orders which returns $this->hasMany(App\Models\Order::class) (or whatever the namespace is for both of them).
That way, you can call $user->orders and get a collection of Order models which will contain only the orders of that particular user.
Definitely read the documentation carefully and learn basic concepts of the framework first and how relational databases function!
You can get a lot of this information just by googling it or reading the documentation of Laravel or any other framework you plan on using! Good luck learning :)
Im trying to figure out the best way to paginate in laravel when i am working with big datasets, the method i am using now is overworking the memory. this is what i am doing: i query from multiple tables, map the results etc, then merge multiple collections, and only after that do i paginate it, i realized though that this is a really bad way of going about this, because i am querying way to much data for no reason, and as the data grows the slower it will become.
the question is what would be the correct way?
i thought maybe i would paginate and then work with the data, the issue is that for instance if i was trying to sort all the merged data by date i wouldn't be getting the proper results because one table may have less data then the other...
here is some of the code to help with clarifying the question
first i will query two tables orders table and transactions table
$transactions = Transaction::all();
$orders = Order::all();
then i will send this all to a action to map it all and format it the way i need to with laravel resources
return $history->execute(['transactions' => $transactions, 'orders' => $orders]);
what this action does is simply map all the transactions and return a resource, then it will map all the orders and return resources for them as well, after which it will merge it all and return the result.
then i take all of this and run it through a pagination action which uses the Illuminate\Pagination\LengthAwarePaginator class.
the results are exactly the way i want them its simply a memory overload.
i tried paginating first instead of doing
$transactions = Transaction::all();
$orders = Order::all();
i did
$transactions = Transaction::orderBy('created_at' 'desc' )->paginate($request->PerPage);
$orders = Order::orderBy('created_at' 'desc' )->paginate($request->PerPage);
and then run it through the action that returns resources.
there are a few issues doing this, firstly, i will no longer get back the pagination data so the app won't know the current page or how many records there are, secondly, if for example the orders table has 2 records, and the transactions table has 10 records, event though the dates of the orders table is after those of the transactions table they will still get queried first.
Use chunk method or paginate
Read documentation.
LaraCSV uses Laravel Collections to easily export csv files from an Eloquent Model. The table I'm extracting the CSV from has 3 FKs from another table. The fields are ['Operator','Supervisor','Escort'] which relate to the PERS_ID from another table.
I need to create a Collection that considers the join clause needed for these 3 fields to contain the full name of the workers, instead of just the PERS_ID.
I've tried the following:
$excesos = ExcesosVelocidad::all();
Which gives me a Collection but does not allow me to perform the JOIN clause needed to bring the full names of the workers. Is there a way to do this?
You can use joins like this:
$excesos = ExcesosVelocidad::join('x', 'x.x', '=', 'x.x')->get();
I've just started using Laravel and I'm coming from a different system using an existing database. In this system there are 2 users table, one stock with the CMS and one custom one.
I want to create an Eloquent model which retrieves data from both tables into one model. I know I can use the following to create a relationship.
$this->hasOne('App\SecondUser', 'id', 'id);
But this results in 2 sql queries, and I want to join results from 2 tables before returning the model, in one join statement. How do I do this?
That might be a bit more complicated that you would expect.
First of all you have to use \DB facade to join the two collections(arrays) and then recreate the Eloquent collection from these arrays using Collection's make method.
More info about the Collection class here
An easier way might be to join them using standard laravel relationships and user something like Model::user->with('relation')->get.
But this will still create 2 queries (still relatively fast).