I have two foreign key related to the same table
When I try to add these two columns to datatable all data resolve from only the first one of them.
My code
cities
$table->id();
$table->string('name');
trips
$table->id();
$table->foreignId('from_ctiy_id')->references('id')->on('cities');
$table->foreignId('to_ctiy_id')->references('id')->on('cities');
in Trip model I make two relationships
public function from_ctiy()
{ return $this->belongsTo(City::class, 'from_ctiy_id'); }
public function to_ctiy()
{ return $this->belongsTo(City::class, 'to_ctiy_id'); }
It works fine I can access to these two columns normally
$trip->from_city->name;
$trip->to_city->name;
But when I create columns in livewire-datatable
Column::name('from_city.name')->lable('From'),
Column::name('to_city.name')->lable('To'),
I get two columns table the same data from only the first one of them
From
To
Fcity
Fcity
Fcity
Fcity
While should I get Fcity and Tcity
U have to build manually the join query like below.
public function builder()
{
return Trip::query()
->leftJoin('City as c1', 'from_ctiy_id', 'c1.id')
->leftJoin('City as c2', 'to_ctiy_id', 'c2.id');
}
public function columns()
{
return [
Column::name('c1.name')->label("From"),
Column::name('c2.name')->label("To")
];
}
Related
I would like to implement an order column (that will be used for determining hierarchy for the entities, both in backend and frontend). Is there a nice way to do this on the migration level?
So that when a new model is saved, the highest number of the order column will be found - but only for the models that share shop_id. So if I add models like this:
// First model should get order = 1
$priceExceptionA = new PriceException();
$priceExceptionA->shop_id = 1;
$priceExceptionA->amount = 100;
$priceExceptionA->save();
// Second model should get order = 2
$priceExceptionB = new PriceException();
$priceExceptionB->shop_id = 1;
$priceExceptionB->amount = 100;
$priceExceptionB->save();
I would like to find a way to implement this behavior already through the migration:
public function up()
{
Schema::create('price_exceptions', function (Blueprint $table) {
$table->id();
$table->integer('shop_id')->unsigned();
$table->integer('amount')->nullable();
// Find the highest order value for rows with the same shop_id and increment this by one
$table->integer('order')->default(////)
$table->timestamps();
$table->softDeletes();
$table->foreign('shop_id')->references('id')->on('shops')->onDelete('cascade');
});
}
I do not believe SQL can what you want to do with the default functionality.
Instead there is a simple solution using model events, that secures all models will get these order values. The creating events, is called before the model is saved to the database and therefor all models will get the order set.
public static function boot()
{
static::creating(function(PriceException $priceException)
{
$priceException->order = ($priceException->shop->priceExceptions()->max('order') ?? 0) + 1;
});
}
This can create race conditions a way to combat this is to use a lock to secure you don't get duplicate order numbering. If you work on a load balanced setup the cache should be a shared redis server.
static::creating(function(PriceException $priceException)
{
Cache::lock($priceException->shop_id)->get(function () use ($priceException) {
$priceException->order = ($priceException->shop->priceExceptions()->max('order') ?? 0) + 1;
});
});
I got 3 tables. Table 1 & 2 has their ids as foreign keys in third one(pivot).
Relations for first one is
$this->hasMany("App\Pivot","game_id");
, second is
$this->belongsToMany("App\Pivot","army_id");
and pivot has relationships with both of them i.e belongsTo.
My schema:
I tried accessing it in controller of first one like this:
$games= Game::with("armies")->get();
Result that i get is array of games where instead of individual army data , i get collection from pivot table.
I can loop through it and get it that way, is there more elegant way of doing it?
If you are using pivot table this is the way how to do it.
Games Model
public function armies()
{
return $this->belongsToMany(App\Armies::class, 'pivot_table', 'game_id', 'army_id');
}
Armies Model
public function armies()
{
return $this->belongsToMany(App\Games::class, 'pivot_table', 'army_id', 'game_id');
}
Access the relationship like this..
Controller
App\Games::first()->armies()->get();
or
App\Games::first()->armies
or
App\Games::find(1)->armies
If you're going to use an intermediate table like that I'd probably do something like this:
Games model
public function armies()
{
return $this->belongsToMany('App\Armies');
}
Armies model
public function games()
{
return $this->belongsToMany('App\Games');
}
I'd keep the table structures all the same but rename the "pivot" table to armies_games since this is what Laravel will look for by default. If you want to keep it named Pivots, you'll need to pass it in as the second argument in belongsToMany.
With this, you don't really need the Pivot model, you should just be able to do:
$armies = Game::first()->armies()->get();
or
$armies = Game::find(3)->armies()->orderBy('name')->get();
or
$game = Game::first();
foreach ($game->armies as $army) {
//
}
etc.
Background:
In my application, Users can own Files. It used to be that a File belongs to a single User, so I used a one-to-many relationship. Now, the requirements have changed, and my relationship needs to become many-to-many.
Previously, the data structure looked like this:
files
(
id,
user_id
...
);
and the new data structure looks like this:
files
(
id,
...
);
file_user
(
id,
file_id,
user_id,
);
Problem:
I created a migration to change my data structure, like this:
public function up()
{
Schema::create('file_user', function (Blueprint $table) {
$table->increments('id');
$table->timestamps();
$table->string('file_id', 36);
$table->string('user_id', 36);
});
}
Then, I set up the relationship in the corresponding models. Now i need to convert the old data into the new data structure. That means taking all the existing Files, and creating a new record in the file_user table. The code itself is simple:
foreach(File:all() as $file) {
$file->users()->attach($file->user_id);
}
I want to run this code alongside the migration, so that after running the migration, the table will populate. However, when I try to put it directly in the migration file like this:
public function up()
{
// create table
Schema::create('file_user', function (Blueprint $table) {
$table->increments('id');
$table->timestamps();
$table->string('file_id', 36);
$table->string('user_id', 36);
});
// convert old data
foreach(File:all() as $file) {
$file->users()->attach($file);
}
}
I get an exception:
PDOException: SQLSTATE[42P01]: Undefined table: 7 ERROR: relation "file_user" does not exist. It seems like the table has not been created yet at the time when the code is trying to run.
Question:
Is there a way that I can put the conversion code inside the migration file to make it work like expected? Or is there a better way to achieve this?
Try to create a second migration file, insert the // convert old data foreach(File::all() as $file) ... part there and migrate the two files together.
I have some working queries that are not ideal and I'd like to try perform them the Eloquent way to tidy it up.
I think I've got the relationships defined correctly but I can't figure out how to write the queries and store them in variables in the controller. I need to return these variables back to the view because I json encode them for use in JavaScript.
Here's what I have in my controller:
public function show($idProject)
{
$project = ProjectsModel::with('user')->where('idProjects','=',$idProject)->first();
$objsettings = ObjSettingsModel::where('idObjSettings','=',$project['ObjSettingsID1'])->first();
$obj = ObjModel::where('idObjs','=',$objsettings['Objs_idObjs'])->first();
return view('project')->with('project',$project)->with('obj',$obj)->with('objsettings',$objsettings);
}
The naming conventions are a bit off so here's what this does.
I pass the $idProject to the controller from a link on my index page where I've looped through and paginated all rows from the Projects table.
The first query finds the project row where it's id (idProjects) matches the variable passed from the index page via the link (idProject). I've also successfully pulled the related user row from the user table using an eloquent relationship.
The next query pulls from an ObjSettings table which stores a number of settings values for an object which is shown on the page. I match the idObjSettings column of the ObjSettings table to the previously pulled $project['ObjSettingsID1'] which is essentially the foreign key in the projects table. There can be several ObjSettings for each Project.
The 3rd query pulls from the Obj table which stores details about an object. These are static details on objects such as name or size for example. I match the idObjs column to the previously pulled $objsettings['Objs_idObjs'] which is the foreign key in the ObjSettings table. One Obj can have many ObjSettings which are used in other Projects.
Here's how I'm passing the php variables to JS:
<script>var obj = #json($obj);</script>
<script>var objsettings = #json($objsettings);</script>
Here are my relationships
ProjectsModel
public function user()
{
return $this->belongsTo('App\User', 'Username', 'id');
}
public function objsettings()
{
return $this->hasMany('App\ObjSettingsModel', 'idObjSettings', 'ObjSettingsID1' );
}
ObjSettingsModel
public function objs()
{
return $this->belongsTo('App\ObjsModel', 'Objs_idObjs', 'idObjs');
}
public function projects()
{
return $this->belongsTo('App\ProjectsModel', 'ObjSettingsID1', 'idObjSettings' );
}
ObjModel
public function objsettings()
{
return $this->hasMany('App\ObjSettingsModel', 'idObjs', 'Objs_idObjs');
}
I've tried a whole range of queries such as:
$project = ProjectsModel::with('user')->with('objsettings.objs')->where('idProjects','=',$idProject)->first();
$objsettings = $project->objsettings;
$obj = $project->objsettings->objs;
but I keep running into issues such as "Property [objs] does not exist on this collection instance." I suppose I'm returning multiple rows in this case? Any help would be appreciated.
You need to loop through objsettings
$project = ProjectsModel::with('user')->with('objsettings.objs')->where('idProjects','=',$idProject)->first();
$objsettings = $project->objsettings;
foreach($objsettings as $objsetting){
$objs = $objsetting->objs;
}
Okey, i seen some posts about this but i don't understand the concept of attach at all, i have three tables:
Llistes(Lists):
$table->increments('id');
$table->string('nom_llista');
$table->integer('user_id')->unsigned();
});
Cancons(Songs):
$table->increments('id');
$table->string('titol');
$table->integer('genere_id')->unsigned();
$table->integer('artista_id')->unsigned();
$table->integer('album_id')->unsigned();
Pivot table: llistes_cancons (lists_songs):
$table->increments('id');
$table->integer('id_canco')->unsigned();
$table->integer('id_llista')->unsigned();
$table->timestamps();
I have two other Classes that i think that are correct, but i''m not sure:
In Canco.php (Song.php):
public function llistescancons_llistes()
{
return $this->belongsToMany('App\Llista');
}
In Llista.php (List.php):
public function llistescancons_cancons()
{
return $this->belongsToMany('App\Canco');
}
So, the question is how can I implement in my controller a function that let me add new record to the pivot table (many to many) and if it's possible another funtion to show the records, i'm newbie in Laravel and it's a bit hard for me.
There's no need to implement methods to add/remove records from the pivot table. Eloquent has attach/detach methods that can do that for you, but first you need to give Eloquent the column names of the pivot table since you are not using Eloquent's column name convention.
In Canco.php (Song.php):
public function llistescancons_llistes()
{
return $this->belongsToMany('App\Llista','llistes_cancons','id_canco','id_llista');
}
In Llista.php (List.php):
public function llistescancons_cancons()
{
return $this->belongsToMany('App\Canco','llistes_cancons','id_llista','id_canco');
}
Then if you want to attach a song to list, you can easily use the song id to do that
$list = App\Llista::find(1);
$list->llistescancons_cancons()->attach($songId);
or the other way around
$song = App\Canco::find(1);
$song->llistescancons_llistes()->attach($listId);