I'm using Laravel 5.7. I have a 'Match' model whose first participant name is returned from a helper function getFirstParticipant(Match $match).
I am trying to get certain matches from DB whose first participants are e.g. 'John'. Is it possible that I use Eloquent query functions to do so for example something like this?
Match::where('firstParticipant', 'John')
or any other solutions?
I am copying my helper function below if it can help to declare the problem:
function getFirstParticipant(Match $match)
{
$structure_id = $match->structure_id;
$seed = $match->matchResult->first_seed;
$placement = Placement::where('structure_id', $structure_id)->where('seed', $seed)->first();
return !empty($placement->player_id) ? $placement->player->username : $placement->team->name;
}
Just sub a variable into the second parameter.
$first = getFirstParticipant(Match $match);
Match::where('firstParticipant', $first->first_name)->get();
Obviously I'm assuming some variable names here such as first_name. But you should be able to follow that. Just use your helper to return a model value and insert that returned value as the second parameter of the where argument.
No, there is no way. Database design issues aside, the only way I can see this working is by using collection methods.
Match::get()->filter(function ($match) {
return $match->firstParticipant == 'John'; // Or is it getFirstParticipant($match) ?
})->all();
# Laravel 6.x introduces LazyCollections
Match::cursor()->filter(function ($match) {
return $match->firstParticipant == 'John'; // Or is it getFirstParticipant($match) ?
})->all();
Related
The code I'm trying to fix looks like this. I have an Hotel class which is used in a query to get all hotels in an area but it doesn't discard those which are not available. There's a method inside which should be an accessor but it's not written the way I expected it to be:
public function isAvailableInRanges($start_date,$end_date){
$days = max(1,floor((strtotime($end_date) - strtotime($start_date)) / DAY_IN_SECONDS));
if($this->default_state)
{
$notAvailableDates = $this->hotelDateClass::query()->where([
['start_date','>=',$start_date],
['end_date','<=',$end_date],
['active','0']
])->count('id');
if($notAvailableDates) return false;
}else{
$availableDates = $this->hotelDateClass::query()->where([
['start_date','>=',$start_date],
['end_date','<=',$end_date],
['active','=',1]
])->count('id');
if($availableDates <= $days) return false;
}
// Check Order
$bookingInRanges = $this->bookingClass::getAcceptedBookingQuery($this->id,$this->type)->where([
['end_date','>=',$start_date],
['start_date','<=',$end_date],
])->count('id');
if($bookingInRanges){
return false;
}
return true;
}
I wanted to filter out hotels using this query. So this is the query from the controller:
$list = $model_hotel->with(['location','hasWishList','translations','termsByAttributeInListingPage'])->get();
Is it possible to pass the range of days to the function?
By the way the first thing I tried was to use the collection after the query and pass a filter function through the collection and after that paginate manually but although it does filter, but apparently it loses
the "Eloquent" result set collection properties and it ends up as a regular collection, thus it doesn't work for me that way.
Maybe the best approach for that is to create a query scope (source) and put all your logic inside of this function.
after that you can call this scope and pass the dates. Example you will create a query scope and paste your code inside of it.
public function scopeisAvailableInRanges($query, $start_date, $end_date) {
}
then you will invoke this query scope in your controller like this.
$list = $model_hotel::isavailableinranges($start_date, $end_date)->with(['location','hasWishList','translations','termsByAttributeInListingPage'])->get();
keep in mind that inside of your query scope you will return a collection. A collection of all your available hotels.
I started learning Laravel and I am trying to achieve the following:
Get data from database and display specific field.
Here is my code in the controller:
public function show()
{
$students = DB::select('select * from students', [1]);
return $students;
}
Here is my route code:
Route::get('', "StudentController#show");
That all works for me and I get the following displayed:
[{"id":1,"firstname":"StudentFirstName","lastname":"StudentLastName"}]
How can I get only the "lastname" field displayed?
Thanks in advance!
DB::select('select * from students')
is a raw query that returns an array of stdClass objects, meaning you have to loop through the array and access properties:
$students[0]->lastname
You can also use the query builder to return a collection of objects:
$collection = DB::table('students')->get();
$student = $collection->first();
$student->lastname;
Lastly, using the query builder, you can use pluck or value to get just the last name. If you only have one user, you can use value to just get the first value of a field:
DB::table('students')->where('id', 1)->value('lastname');
I strongly advise you to read the Database section of the Laravel docs.
$students[0]['lastname'] will return the last name field, the [0] will get the first student in the array.
I would recommend creating a model for Students, which would make your controller something like this:
$student = Students::first(); // to get first student
$student->lastname; // get last names
If you only want the one column returned, you can use pluck()
public function show()
{
$last_names= DB::table('students')->pluck('lastname');
return $last_names;
}
This will return an array of all the students' lastname values.
If you want just one, you can access it with $last_names[0]
As a side note, your show() method usually takes a parameter to identify which student you want to show. This would most likely be the student's id.
There are several ways you can accomplish this task. Firstly, I advise you to use the model of your table (probably Students, in your case).
Thus, for example,to view this in the controller itself, you can do something like this using dd helper:
$student = Students::find(1);
dd($student->lastname);
or, using pluck method
$students = Students::all()->pluck('lastname');
foreach($students as $lastName) {
echo $lastName;
}
or, using selects
$students = DB::table('students')->select('lastname');
dd($students);
Anyway, what I want to say is that there are several ways of doing this, you just need to clarify if you want to debug the controller, display on the blade...
I hope this helps, regards!
I have a Accessor method in Collection Model getSizesAttribute, which returns array of available sizes eg: ['S','L'], Now I need to get Models with have size 'S'. like:
$collections = $collections->where('sizes','S');
But sizes is array, could I manipulate this anyhow so that I could check returns only if sizes have specific size.
I tried making another method getIsSizeAttribute, like:
public function getIsSizeAttribute($size){
return in_array($size,$this->sizes);
}
Now How could I user this in Where condition like
$collections = $collections->where('is_size','S');
Mutators and Accessors only run skin-deep, after the query's already been executed. You could use Collection::filter() as Bangnokia suggests, but that wouldn't give you any performance benefit of actually applying the condition to the initial request.
I think what you're looking for here is a Query Scope. Add something like this to your Model class:
public function scopeSize(\Illuminate\Database\Eloquent\Builder $query, $size)
{
return $query->whereIn('sizes', $this->sizes[$size]);
}
And access it like this:
$collection = $model->size('S')->get();
You should use filter on collection
$collections = $collections->filter(function($item, $index) {
return in_array('S', $item->sizes);
});
I have a custom attribute on my User model that's calculates the length of some other tables and returns an integer value:
public function GetCurrentQueueLengthAttribute()
{
// return int
}
I then have an API endpoint that returns a "Team" with all its users (simple Spark pivot)
public function show($teamId)
{
$query = Team::query();
$query->with('users')->where('id', $teamId);
$team = $query->first();
return $team->users->sortBy('currentQueueLength');
return $team;
}
The issue is that the returned data doesn't change order. There are no errors, just the same order of the users every time.
Is there something I'm missing?
The sortBy function is not to be mistaken by the orderBy function, the first one sorts a collection, the second one alters the sql of the query builder.
To be able to use the sortBy function one first needs to retrieve the collection. These functions can still be chained by using:
return $team->users()->sortBy('currentQueueLength');
optionally one could also use orderByRaw if you are willing to write a custom sql query for the sorting.
i have the following block of code in my Resource Controller:
$travel_company_id = Input::get('travel_company_id');
$transport_type = Input::get('transport_type');
$route_type = Input::get('route_type');
$travelRoutes = TravelRoute::where('travel_company_id', $travel_company_id)
->where('transport_type', $transport_type)
->where('route_type', $route_type)
->get();
Now what this does is it gets travelRoutes based on the parameters supplied. What i want is for it to do is perform a search based on the available parameters, that way if $route_type is empty the search will be performed only on travel_company_id and transport type.
Also if all the parameters are empty then it will simply do a get and return all available records.
I know i can do this with lots of if statements but then if i add a new parameter on the frontend i will have to add it to the backend as well, I was wondering if there was a much simpler and shorter way to do this in laravel.
The where method accepts an array of constraints:
$constraints = array_only(Input::all(), [
'travel_company_id',
'transport_type',
'route_type',
]);
$routes = TravelRoute::where($constraints)->get();
Warning: do not use Input::only() instead of array_only(). They're not the same.
Input::only() fills in any missing items with null, which is not what you want here.
This is pretty hacky and if you spend some time developing a solution I'm sure it could be much nicer. This assumes all the fields in the getSearchFields() function match the input names from the form and database.
/**
* Search fields to retrieve and search the database with. Assumed they match the
* column names in the database
*/
private function getSearchFields()
{
return ['travel_company_id', 'transport_type', 'route_type'];
}
public function search()
{
// Get a new query instance from the model
$query = TravelRoute::query();
// Loop through the fields checking if they've been input, if they have add
// them to the query.
foreach($this->getSearchFields() as $field)
{
if (Input::has($field))
{
$query->where($field, Input::get($field));
}
}
// Finally execute the query
$travelRoutes = $query->get();
}