I have a bookings table with fields:
name | String
from | Datetime
to | Datetime
I select some of those bookings and display them as a list. I also check if the previous booking is less than 30 days apart.
I do this by querying for each booking the previous booking:
#if ($booking->previousBooking()) // Simplified version but you get the idea
The underlying code:
public function previousBooking()
{
return Booking::where('from', '<', $this->from)
->orderByDesc('from')
->first();
}
You might have guessed it already: it adds a query for each booking.
The best scenario would be to kind of eager load the "previous booking" (with) so that it is accessible like:
$booking->previous_booking->from
Is there any possible way to do it like this?
Constraints:
I can't query all bookings, order them by "from" and then just get the previous index
Take a look at this article by Jonathan Reinink. You can apply his solution by simulating a previous_booking_id on your Booking model. Then add the previousBooking() relationship and query that using with('previousBooking'). Let me know if you need any help on the implementation.
Update
Add the following scope to your Booking model:
public function previousBooking()
{
return $this->belongsTo(Booking::class);
}
public function scopeWithPreviousBooking($query)
{
$query->addSelect(['previous_booking_id' => Booking::select('id')
->whereColumn('previous_booking.from', '<', 'bookings.to')
->orderByDesc('from')
->take(1)
])->with('previousBooking');
}
You can now get all your bookings with their previous booking id included using this:
$bookings = Booking::withPreviousBooking()->get();
All bookings should now have a previous_booking_id. We add the with('previousBooking') to the end of the scope as if we query a relation of the booking. Eloquent does not care whether that previous_booking_id is in the database or not, as long as it's available in the model (which we've done by the addSelect() method).
You should now be able to use your requested solution in your view:
$booking->previousBooking->from
Note: you can only access the previousBooking relation if you've applied the scope. If not, the previous_booking_id is not available, and the relation will therefore be null. If you always want to load the previous booking, consider to add it as a global scope. However, I recommend to just apply the scope where it's needed.
Related
I have two forms; the first is the form formers with two fields (name, firstname).
I also have the form trainings with two fields (date_sitting, fk_former).
My problem, if I want to add the other sitting today (07/07/2019), I would like to see only the formers who have no training today.
Here, I retrieve a former who has a sitting today.
Do you think it's possible to get only the formers who have no of sitting for now?
Edit: 10/07/2019
Controller Training
public function index()
{
$trainings = Training::oldest()->paginate(5);
$formersNoTrainingToday = Training::whereDate('date_sitting', "!=", Carbon::today())
->orWhere('date_sitting', null)->get();
return view('admin.trainings.index', compact('trainings', 'formersNoTrainingToday'))
->with('i', (request()->input('page',1) -1)*5);
}
And
public function create()
{
$formers = Former::all();
return view('admin.trainings.create', compact('formers','trainings'));
}
I would like to see only the formers who have no training today.
Sure - you can determine your correct list of candidates to show by using the following query:
$formersNoTrainingToday = Training::whereDate('date_sitting', "!=", Carbon::today())
->orWhere('date_sitting', null)->get();
This should work... but it assumes a few things within your code / db. If this fails, consider a few options to replace the whereDate section above:
Using where:
->where('date_sitting', '!=', \Carbon::today()->toDateString())
Using formatted date if that column on the DB is a different format than Carbon:
->whereDate('date_sitting', "!=", Carbon::now()->format('m/d/Y'))
If you're not using Carbon for some reason, you can try the raw query route for today:
->whereDate('date_sitting', "!=", DB::raw('CURDATE()'))
Bottom line, here are a number of ways to get close to this. But you may need to tweak this on your own to suit your needs. You may need to take Timezone or some hours of difference into account, so you may need to add a range or buffer. But the above should get you close if not all the way there.
HTH
I have a table called rentals, within each row are columns state,city,zipcode which all house ids to another table with that info. There are about 3400 rentals. I am pulling each column to display the states,city and zipcode distinctly. I need to show how many rentals are in each one. I am doing this now via ajax, the person starts typing in what they want to see and it auto completes it with the count, but its slow because of the way im doing it.
$rentals_count = Rentals::where('published',1)->get();
foreach($states as $state) {
echo $state.”-“.$rentals_count->where(‘state’,$state->id)->count();
}
Above is roughly what im doing with pieces removed because they are not related to this question. Is there a better way to do this? It lags a bit so the auto complete seems broken to a new user.
Have you considered Eager loading your eloquent query? Eager loading is used to reduce query operations. When querying, you may specify which relationships should be eager loaded using the with method:
$rental_counts = Rentals::where('published',1)->with('your_relation')->get();
You can read more about that in Laravel Documentation
$rentals = Rentals::wherePublished(true)->withCount('state')->get();
When you loop through $rentals, the result will be in $rental->state_count
Setup a relation 'state' on rentals then call it like this
$rentals_count = Rentals::where('published',1)->with('state')->get()->groupBy('state');
$rentals_count->map(function($v, $k){
echo $v[0]->state->name .' - '. $v->count();
});
Meanwhile in Rentals Model
public function state(){
return $this->hasOne(State::class, 'state'); //state being your foreign key on rentals table. The primary key has to be id on your states table
}
I have an appointments table and an appointment_members table and my users need to be able to get a collection of appointments by searching with a "member_id", which could be a Person, Incident or CustomerID. The appointment_members table has member_id and appointment_id columns, so the member_type (also a column) is irrelevant. This all set up by a previous dev and what is missing are the relationships on the Eloquent models. I'm just creating a simple GET route that needs to return any/all appointments by that member_id. Each row has one appointment, so if I were to pass in a member_id that returned 10 results, some could have appts and others not, but at the end of the day I just need a collection of appts that are related to that member_id. Here's a screenshot of the appointment_members table:
If I create a simple hasOne relationship to appointments on appointment_members:
public function appointments()
{
return $this->HasOne(Appointment::class, 'id', 'appointment_id');
}
I can get a collection of appointment_members with it's respective appointment, but not sure how I boil it down to just getting the appointments. One workaround I have is to use that HasOne and then pluck/filter the appointments:
$appointmentMembers = AppointmentMembers::where('member_id', $request->input('memberId'))->get();
$appointments = $appointmentMembers->pluck('appointments')->filter();
Curious if anyone might see a better way to go about this. Thanks!
I'm possibly not understanding, but I would probably take the simplest approach here if the member type is not important.
The table is already set up to handle either a belongsToMany or a morphMany, so create the relationship on the Member class (or if you don't have a parent member class, stick it on each of the types Person, Incident, etc. You can also do this via poly, of course, but this is a simple example to get what you need):
public function appointments()
{
return $this->belongsToMany(Appointment::class)->withPivot('member_type');
}
And then just query on the member object you need appointments for (having poly would make this one step):
$allAppointmentsForID = $member->appointments();
$appointments = $allAppointmentsForID->wherePivot('member_type', $whateverClassThisIS);
The above takes member_type into account. If this doesn't matter, you can just use the top line.
Your original db is setup to handle polymorphic relations, so if you wanted more than the appointment you can set it up this way as well. For now, you'll need to add the TYPE to the query to cover the different classes.
If the member type is important, polymorphic might be something like this on the Member class:
public function appointments()
{
return $this->morphMany(Appointment::class, 'memberableOrmember_typeOrWhatever');
}
Then you can query on the member object with just one line
$appointments = $member->appointments();
I've got a many to many relationship between a student and an institution_contact.
students should only ever have two institution_contacts and I have an attribute on the pivot table named type to be set as 1 or 2.
So, my pivot table looks like this:
institution_contact_student: id, institution_contact_id, student_id, type
I've run into difficulty in deciding how to approach the issue of adding/updating the pivot table. Let's say I have 100 students and I want to assign them a contact with the type of 1.
My current solution is to delete the contact then add it:
$students = Student::all(); // the 100 students
$contactId = InstitutionContact::first()->id; // the contact
foreach ($students as $student) {
// remove existing contact
$student
->institutionContacts()
->newPivotStatement()
->where('type', 1)
->delete();
// add new contact
$student
->institutionContacts()
->attach([$contactId => ['type' => 1]]);
}
However, I'm thinking that this is going to hit the database twice for each student, right? So would I be better off creating a model for the pivot table and removing all entries that matched the student id and the type then simply adding the new ones? Or would creating a model for the pivot table be considered bad practice and is there a better way of accomplishing this that I've missed?
Please note the reason I'm not using sync is because I'm relying on the type attribute to maintain only two contacts per student. I'm not aware of a way to modify an existing pivot without causing issues to my two contacts per student requirement.
Edit:
Instead of creating a model I could run the following code to perform the delete using DB.
DB::table('institution_contact_student') // the pivot table
->whereIn('student_id', $studentIds)
->where('type', 1)
->delete();
If I have understood your question correctly then you can use the updateExistingPivot method for updating your pivot table.But first of course you have to define the pivot in your relationship. For instance,
public function institutionContacts(){
return $this->belongsToMany('institutionContact')->withPivot('type');
}
after this, all you have to do is use the following code:
$student
->institutionContacts()
->updateExistingPivot($contactId, ["type" => 1]);
Hope this helps.
Some help with many to many relationships in Laravel:
Using the example for roles and users - basically:
a table for all the roles
a table for the users
and table with user_id and role_id.
I want to add to the third table, eg Year. basically the pivot table will have user_id, role_id and year_id.
I want to be able to make a query to pull for example all users assigned a specific role in a specific year. Eg All users with role_id = 2, and year_id = 1.
Any help will be appreciated
Before answering, I would like to suggest you not to put year on database like this.
All your tables should have created_at and updated_at which should be enough for that.
To filter users like you want. You could do this:
// This queries all users that were assigned to 'admin' role within 2013.
User::join('role_users', 'role_users.user_id', '=', 'users.id')
->join('roles', 'roles.id', '=', 'role_users.role_id')
->where('roles.name', '=', 'admin')
->where(DB::raw('YEAR(role_users.created_at)', '=', '2013')
->get();
This example may not be the precise query you are looking for, but should be enough for you to come up with it.
The best way to achieve a three way relation with Eloquent is to create a model for the table representing this relation. Pivot tables is meant to be used for two way relations.
You could have then a table called roles_users_year which could have data related to this 3 way relation like a timestamp or whatever...
A very late answer to a very old question, but Laravel has supported additional intermediate (pivot) table columns of at least Laravel 5.1 judging from the documentation, which hasn't changed at least through Laravel 6.x.
You can describe these extra columns when defining your many-to-many relationship:
return $this->belongsToMany(Role::class)->withPivot('column1', 'column2');
or in your case, the below would also do the job:
return $this->belongsToMany(Role::class)->withTimestamps();
which you can then access via the pivot attribute on your model:
$user = User::find(1);
foreach ($user->roles as $role) {
echo $role->pivot->created_at;
}
Note that the pivot attribute is on the distant relationship model (a single Role) and not on the relationship itself.
To get all the Roles assigned to Users in any given year, you might create a special relationship:
// User.php
public function rolesInYear($year) {
return $this->belongsToMany(Role::class)
->wherePivot('created_at', '>=', Carbon::create($year))
->wherePivot('created_at', '<', Carbon::create($year + 1));
}