I'm trying to send API with certain number of records
$category->products
I tried to use limit() or take() but it fails
so is there any smart solution than go to pivot and select it with limit ??
Copy data to a new collection.
$collection =$category->products;
you can now send the number of times you want using take ().
for example;
$collection->take(5);
if your question is different please explain it more clearly.
I found the solution I was easy
$category->products()->limit(2)->get()->all()
that's all
Related
I am new to DynamoDB so I'm still trying to understand how to use it, but I have what I believe is a simple task but I'm not sure how to address it.
I need to create a table to store categorized questions in which I need to store a click counter. So let's say something like this:
ID: 1
Question: What is this?
Category: General
Clicks: 100
Now, the problem is I need an optimized way to get the most general clicked questions and the most clicked questions by category, let's say a top 10.
In a classic SQL style it would be something like this:
SELECT ID, Question
FROM Questions
ORDER BY Clicks DESC
LIMIT 10
Can anyone point me in the right direction on how to structure the table? I tried the sorting but it always requires a hash key condition, so I don't understand how I can get this done as I need the top 10 results and not a single one.
Thanks in advance!
How are you accumulating the clicks, if you are able to figure out how you accumulate the clicksstream onto the table correctly that will be your answer.
You will need to implement a mechanism that maps incoming clicks to the item record being clicked on and increment it using an atomic counter. With this you will be able to then create a sparse index and sort it in descending order to get what you need.
I am struggling with a pretty difficult thing and hope you can help me out.
Right now I've got the following:
$ads = Ad::where('status', 1)
->whereIn('ad_type', [1, 2, 3])
->where('expire_at', '>', date('Y-m-d H:i:s'))
->where('special_ad', 'standard_ad')
->orderByRaw(DB::raw("FIELD(ad_type,2,3,1)"));
Info:
This is working because it is an Eloquent Collection and I can Paginate this (needed for my Infinite Scroll)
But now I want to shuffle the ad_types in itself, meaning:
ad_type 1 could have, let's say, 30 entries. They will all be returned in the usual order. I want to shuffle those 30 every time I run this query.
I thought about doing ->toArray(); but then again, no pagination (Pagination only works on Eloquent Queries right?)
Then I thought, hey, let's merge this.
But as soon as I did that, the returned collection is no longer an Eloquent Collection but a Support Collection (right? I am not 100% sure it is a Support Collection) thus the Pagination does not work anymore.
I read upon many posts as how to solve this problem, and figured out one solution may be to "create my own paginator instance"
But heck, I am not that good yet. I do really not know, even after studying the laravel documentation, how to create my own paginator.
Important Infos you might need:
Using Laravel 5.2
$ads are dynamical, meaning depending on the case, the requests sent with Ajax, the query might differ at a later point (something might get included).
Thank you very much for your time reading this and hopefully, you can help me and future readers by solving this particular problem.
Greetings, and a great weekend to all of you.
Firstly just to note:
Pagination does not only work for database queries. You can manually paginate using LengthAwarePaginator but manually is the keyword here. The query builder (not Eloquent) can do it automatically for you using paginate.
You can "shuffle" the results by doing something like
$ads = Ad::where('status', 1)
->whereIn('ad_type', [1, 2, 3])
->where('expire_at', '>', date('Y-m-d H:i:s'))
->where('special_ad', 'standard_ad')
->orderByRaw("FIELD(ad_type,2,3,1)")
->orderByRaw("RAND()");
This will order by the ad_type field first and order by a random number (different for every row) as a secondary sort.
I have 2 queries, I want to know which is the best query
Model::select('id')->where('status','1')->first();
Model::lists('id')->where('status','1')->first();
Please let me know
The first one is better because it gets only one object. But a better way to get ID of the first row with status = 1 is to use the value() method:
Model::where('status', '1')->value('id');
The second query is bad because it loads all IDs into memory and then filters them.
Is it possible to chain options when using maximum?
I have a PhoneStats class and I want to pull the name from a few columns who have the maximum value in the table. For example if I run
PhoneStat.maximum('calls')
I get the value I expect but I would like to get maximum value as well as the id of the user in that record. Is it possible to use pluck or collect for something like this?
Thanks spickermann
Thanks. Below got me exactly what I needed.
PhoneStat.order('calls DESC').pluck(:name).first
You have to write this a bit more detailed:
PhoneStat.order('calls DESC').first
So I'm extremely new to Linq in .Net 3.5 and have a question. I use to use a custom class that would handle the following results from a store procedure:
Set 1: ID Name Age
Set 2: ID Address City
Set 3: ID Product Price
With my custom class, I would have received back from the database a single DataSet with 3 DataTables inside of it with columns based on what was returned from the DB.
My question is how to I achive this with LINQ? I'm going to need to hit the database 1 time and return multiple sets with different types of data in it.
Also, how would I use LINQ to return a dynamic amount of sets depending on the parameters (could get 1 set back, could get N amount back)?
I've looked at this article, but didn't find anything explaining multiple sets (just a single set that could be dynamic or a single scalar value and a single set).
Any articles/comments will help.
Thanks
I believe this is what you're looking for
Linq to SQL Stored Procedures with Multiple Results - IMultipleResults
I'm not very familiar with LINQ myself but here is MSDN's site on LINQ Samples that might be able to help you out.
EDIT: I apologize, I somehow missed the title where you mentioned you wanted help using LINQ with Stored Procedures, my below answer does not address that at all and unfortunately I haven't had the need to use sprocs with LINQ so I'm unsure if my below answer will help.
LINQ to SQL is able hydrate multiple sets of data into a object graph while hitting the database once. However, I don't think LINQ is going to achieve what you ultimately want -- which as far as I can tell is a completely dynamic set of data that is defined outside of the query itself. Perhaps I am misunderstanding the question, maybe it would help if you provide some sample code that your existing application is using?
Here is a quick example of how I could hydrate a anonymous type with a single database call, maybe it will help:
var query = from p in db.Products
select new
{
Product = p,
NumberOfOrders = p.Orders.Count(),
LastOrderDate = p.Orders.OrderByDescending().Take(1).Select(o => o.OrderDate),
Orders = p.Orders
};