Laravel 5.4 table relationship between 3 small tables - laravel

I have a recently started learning Laravel 5.4, I am having trouble with my 3 way table relationship, I've looked at a few articles online regarding many to many, but this relationship is just a "hasOne" on both sides.
Could anyone give me a helpful hint as to how to structure my table relationship, here is the PK/FK relationship:
Users table (id)
Listings table (id, user_id)
Insights table (id, listing_id) - one insight row per listing only.
And the models below:
Users Model
class User extends Model
{
public function listing()
{
return $this->belongsTo('App\Listing');
}
}
Listing Model
class Listing extends Model
{
public function insight()
{
return $this->hasOne('App\Insight');
}
}
Insight Model
class Insight extends Model
{
public function listing()
{
return $this->hasOne('App\Listing');
}
}
And what I am trying to achieve is to query the users own listings, with each listings current insights.
Thanks a bunch.
Simon.

User model
class User extends Model
{
public function listing()
{
return $this->hasOne('App\Listing');
}
}
Listing Model
class Listing extends Model
{
public function insight()
{
return $this->hasOne('App\Insight');
}
public function user()
{
return $this->belongsTo('App\User');
}
}
Insight Model
class Insight extends Model
{
public function listing()
{
return $this->belongsTo('App\Listing');
}
}
And if you want query users with Listing and Insight
$users = User::with(['listing', 'listing.insight'])->get();
foreach($users as $user) {
$user->listing->insight;
}

class User extends Model
{
public function listing()
{
return $this->hasMany(Listing::class);
}
}
class Listing extends Model
{
public function insight()
{
return $this->hasOne(Insight::class);
}
public function user()
{
return $this->belongsTo(User::class);
}
}
class Insight extends Model
{
public function listing()
{
return $this->belongsTo(Listing::class);
}
}
$users = User::with('listing.insight')->get();
foreach($users as $user) {
$user->listing->insight;
}

Related

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name
organisation_members
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organisation_id (FK to organisations)
user_id (FK to users)
unqiue(organisation_id, user_id)
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name
A user can be a member to many organisations.
My models are written as follows
class User extends Model {
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return $this->hasMany(OrganisationMember::class);
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public function organisations()
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// TODO: how do I do this one
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return $this->belongsTo(Organisation::class);
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return $this->belongsTo(User::class);
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How can I write a relationship method in the User model for organisations?
Thanks to #matiaslauriti comment the answer is:
class User extends Model {
public function organisationMembers(): HasMany
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Get all records from another table with pivot

I have three tables:
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id | comment_id | link_id
links
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Here are my current class relationships (they may be wrong):
Comment.php:
class Comment extends Model
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return $this->hasMany('App\CommentLink', 'comment_id', 'id');
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class Link extends Model
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What do I need to do here to make this work?
You have the right idea, just using the wrong class names.
class Link extends Model
{
public function comments()
{
return $this->belongsToMany('App\Comment');
}
}
class Comment extends Model
{
public function links()
{
return $this->belongsToMany('App\Link');
}
}
You don't actually need to have a class for your pivot table, but you can if you want.
This is quite a good guide on how to do this.
https://laraveldaily.com/pivot-tables-and-many-to-many-relationships/

One to Many Relationship Over Pivot Table

I have existing data in the database, and I want to create a one-to-many relationship. How can I limit or simulate a one-to-many relationship when I'm using a pivot table?
I want to get the data from the pivot table, so I thought it could be done like this.
class Asset extends Model {
public function publisher() {
return $this->belongsTo(Publisher::class, 'asset_publisher');
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}
-
class Publisher extends Model {
public function assets() {
return $this->hasMany(Asset::class, 'asset_publisher');
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}
A possible way to simulate the one-to-many is creating a model for the pivot table "AssetPublisher" so you will now have
class Publisher extends Model {
public function assets() {
return $this->belongsToMany(Asset::class, 'asset_publisher');
}
}
class AssetPublisher extends Model {
public function publisher() {
return $this->belongsTo(Publisher::class);
}
}
class Asset extends Model {
public function assetPublisher() {
return $this->hasOne(AssetPublisher::class)->with('publisher');
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return $this->assetPublisher->publisher;
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I have the following models: Merchant, Product and Store:
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class Merchant extends Model
{
public function products() {
return $this->hasMany('App\Product');
}
}
Product:
class Product extends Model
{
public function merchants() {
return $this->belongsTo('App\Merchant');
}
public function stores() {
return $this->belongsTo('App\Store');
}
}
Store:
class Store extends Model
{
public function products() {
return $this->hasMany('App\Product');
}
}
In my MerchantController, I have the following method show():
public function show() {
$merchants = Merchant::selectRaw('merchants.*, REPLACE(abstract, \'[[name]]\', name) AS abstract')
->with('products')
->where('active', 'yes')
->Paginate(10);
dd($merchants);
//return view('merchants', compact('merchants'));
}
How can I access the stores, the several products are in? I tried ->with(['products', 'stores']) and got an error:
Call to undefined relationship [stores] on model [App\Merchant].
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in your Merchant model
add this relationship
public function stores()
{
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Laravel Eloquent Relationship Through Another Table

I have the following database tables:
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number
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name
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$teams = [];
$standings = $season->standings;
foreach($standings as $standing){
$teams[] = $standing->team;
}
Is there a way I could do this using Eloquent relationships? I have tried HasManyThrough with no success. These are what my models look like currently:
class Season extends Eloquent{
public function standings(){
return $this->hasMany('Standing');
}
}
class Standing extends Eloquent{
public function team(){
return $this->belongsTo('Team');
}
}
class Team extends Eloquent{
public function standings(){
return $this->belongsToMany('Standing');
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}
Your relationships look a little off. Here is all the relationships you should need though only the belongsToMany ones are required for this specific scenario of finding all the teams in a season.
class Season extends Eloquent {
public function teams()
{
return $this->belongsToMany('Team', 'Standings');
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public function standings()
{
return $this->hasMany('Standing');
}
}
class Team extends Eloquent {
public function seasons()
{
return $this->belongsToMany('Season', 'Standings');
}
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{
return $this->hasMany('Standing');
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class Standing extends Eloquent {
public function team()
{
return $this->belongsTo('Team');
}
public function season()
{
return $this->belongsTo('Season');
}
}
You would use the belongsToMany relationship rather than a hasManyThrough to query all the teams in a season. That would look something like...
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foreach($season->teams as $team) {
echo $team->name;
}

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