So I have a User table and a History table with User hasMany Histories, and I'm trying to implement pagination on the user table.
My problem is that I have search, and some of the things one can search by are things in the History table. Is there a way to filter pagination results based on data in a table associated by hasMany? Containable, which initially seemed like a solution, allows such filtering but only in the retrieval of associated data, not the records themselves (unless I'm missing something?)
Has anyone had to solve this before?
Since it's a hasMany relationship, that means Cake will need to make 2 separate queries: 1 on the users table, and one on the histories table to retrieve all the associations. Since the History data isn't being retrieved until the 2nd query, then your 1st query cannot be filtered via WHERE conditions for fields found in the History model.
To resolve this, you can do one of two things:
Perform pagination on History using Containable (since History belongsTo User, meaning only 1 query will be performed).
Perform pagination on User the way you're already doing, except perform an ad-hoc join to History such that it's no longer a hasMany relationship.
e.g.:
$this->User->bindModel(array('hasOne' => array('History')));
$this->paginate['User']['contain'][] = 'History';
$this->paginate('User', array('History.some_field' => 'some_value'));
Related
I have a many-to-many relationship between an incident model and a Patient model. An incident can have many patients and a patient can be involved in many incidents.
Should it occur that a user creates duplicates of a patient model we want to be able to merge those two patient models into one. This means that I want to move the incidents that patient 1 is involved in to patient 2 including additional attributes that are sitting on the pivot table.
I've tried something as simple as
Casualty::where('patient_id', $patientOne->getKey())->update(['patient_id' => $patientTwo->getKey()]);
But this doesn't work. Using the updateOnExistingPivot() method would mean I need to iterate over every incident for patient 1 and run a separate DB query to update the patient to patient 2.
I've also tried updating the record like this
$patientOne->incidents()->update(['patient_id' => $patientTwo->getKey()]);
This also doesn't work because there is no patient_id column on the incidents table.
How can I achieve this or am I doing something wrong?
Not sure if I understood you, you want to group more patients into the same accident? You could go with the belongsToMany relation and make one pivot table. Then, when you want to update the data simply use the sync method.
You can also try storing them with json_encode() in one column which will hold only users ID's and later on retrieve them.
Sorry, can't give more info since the question is not described that well.
I have a table like this:
payments
-id
-client_id
-vendor_id
-product_id
-item_id
-..._id
Using Laravel's eager loading, I can do this ->load('client', 'vendor' ... ) and load the relationships for all the returned rows of payments. But I've noticed that for example when there are no values in payments for vendor_id the eager loading query for the "vendor" relationship still happens, as below:
select * from `vendors` where `vendors`.`id` in ('')
The in ('') I understand should be filled with the values for vendor_id in the payments table, but since there were none the above query should not happen, right?! Is that a bug in Laravel?
The problem is that i got like 20 [x]_id columns in this payments table, and in each row only a couple (varies for each row) [x]_id columns have values, and I don't want to make 20 extra eager-loading queries, just the ones needed based on the actual existence of these ids!
When you are doing lazy eager loading, laravel does not know if records are present or not. If not present laravel returns empty collection.
If you want to filter out at the start itself to show only payments having vendors and clients etc, you can do :
$payments : Payment::whereHas('vendors')->whereHas('clients')->get();
Above will give you only payments which contain at-least one vendor and 1 client.
Also, you are using load() which is lazy-eager loading. It is designed so that you can get the primary collection first and later when and if you need, then only get the relation collection.
Check for with() if you do not want to lazy-eager load.
Also, if you want to avoid eager loading, you can go for join but again then you wont be using defined relations.
I have a DB, "views," with many, many entries. I also have a "Courses" table, which these views are one-many related to. In Laravel Nova, I can get a metric of all views over time for a course with some code like this:
public function calculate(Request $request)
{
return $this->countByDays($request, view::where('viewable_id', $request->resourceId));
}
In this case, viewable_id is the id of the course, and $request->resourceId gives the ID of the course to sort by. Pretty simple.
However, now things get a little difficult. I have another model called Teachers. Each Teacher can have many courses, also in a one-many relationship. How do I get a metric of views over time for all the courses that teacher teaches?
I assumed the simplest way to do this would be to create a Laravel Collection with all courses the Teacher teaches (not exactly efficient), and then select all views in the database where viewable_id matches one of the courses in that list. Of course, by posting this, I couldn't figure out how to do that.
Of course, once this is figured out, I'd love to do the same thing for Categories (though that should function in a very identical manner to Teachers, so I don't need to ask that question).
How do I get a metric of views over time for all the courses that teacher teaches?
This should be the "countByDays" of views where the viewable_id is in the list of course ids that the teacher teaches.
An SQL query statement to achieve that is given below:
select * from "views"
where "viewable_id" in (select "id" from "courses" where "teacher_id" = ?)
The Eloquent query should be similar to:
$this->countByDays($request,
view::whereIn(
'viewable_id',
Course::with('teacher')
->select('id')
->where('teacher_id', $request->resourceId)
)
);
Ok so I have an app that searches through course applications which each belong to an applicant. When I search the applications for a course title it returns the required result set but I would like to sort it by the applicant's date of birth.
How can I do this? I've tried sorting the collection doing $applications->sortBy('applicant.dob') but this seems to just order it by each applicant not the overall collection.
Edit
Here's all of my code... http://laravel.io/bin/PD81z
Any one have an idea how I can approach this?
Thanks!
OK
Your table course and table applicant are actually many-to-many relationship
For this to work, table course_applitions serves as a proxy to link the two table.
see the post, especially the part about many-to-many relationships
http://scotch.io/tutorials/php/a-guide-to-using-eloquent-orm-in-laravel
When fetching results from related tables using the above way, you can always add sort options.
Cheers!
I have a site that scrapes all the episodes from tv.com from certain series.
So my database has a User table, a Show table, an Episode table, a Show_User table (to associate shows with users, HABTM), an Episode_Show table (to associate episodes with shows, HABTM), a Episode_User table (to associate episodes with shows, only as a way of marking them as 'watched').
Now I want to add a way of marking an episode as 'downloaded' too.
So at the moment, the Episode_User table has two fields, Episode_Id and User_Id. Should I create a new table entirely for this? Or just add a field to the Episode_User table?
I'm using CakePHP's automagic features, and don't particularly want to break it. But if I have to, I have to...
Thanks for any advice.
I don't see why you would want to create a new table for episodes a user has downloaded. To me it would make the most sense to modify the Episode_User table to have a field for watched and a field for downloaded, since it's all relating back to the same pair of entities, users and episodes.
However, any time I've stored information about a relationship between two tables in that manner, I've found that regardless of the framework I'm using, the ORM inevitably become more complicated, but I don't think there's any way around there.
With CakePHP for handling those kinds of complicated situations, read up about the model behavior, Containable. It's not very well documented in the CakePHP book, but is really quite useful in a situation where you need to use the fields in Episode_User, for example, if you needed to find all of the users that had watched a particular episode, but not downloaded it.
Also, it occurred to me, while reading your post, that you could possibly make your data model more simple by having a hasMany relationship between shows and episodes. An episode will never belong to more than one show, so your episodes table could just have another field, show_id, which related back to the show table, and you wouldn't even need the Episode_Show table.