I have my class "Product_reviews", which is binded to the class "Products" like this:
Products.php:
public function product_reviews()
{
return $this->hasMany('App\Product_reviews');
}
Product_reviews.php:
public function products()
{
return $this->belongsTo('App\Products');
}
Foreign key for table "Product_reviews" is 'product_id'.
So, in the controller I'm trying to get all data:
$products = Products::with('product_reviews')->get();
And... I have an error saying that product_id can't be found:
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'product_reviews.products_id' in 'where clause' (SQL: select * from `product_reviews` where `product_reviews`.`products_id` in (1, 2))
Correct me if I'm wrong, but I think the query builder is adding '_id' to the class' name. It can be fixed by going to the table "product_reviews" and changing 'product_id' by 'products_id'... Or maybe I could pass all classes' and tables' names to singular.
So my question is: What other options do I have in order to make the query builder know the proper column's name?
Your models should be named in the singular form, and then Laravel will not attempt to use the plural form of the column name in the generated SQL query.
In your case, the Products model should be called Product. Remember that a model represents one record in your database, so the singular form is correct.
You overwrote this behaviour by manually setting the foreign field in your $this->hasMany(..) relationship, which skirted around the issue, but didn't fix the underlying cause.
Additionally, you should avoid using snake_cased class names, as it violates PSR. Your Product_reviews model should be called ProductReview.
Ok, I got it:
In Products.php:
return $this->hasMany('App\Product_reviews');
I added 2 more parameters to the function hasMany, like this:
return $this->hasMany('App\Product_reviews','product_id','id');
These parameters specify the id's names.
This post really helped:
laravel-hasmany-and-belongsto-parameters
Anyhow I think it may be good in long terms to do what Davit and hktang say and rename my classes with singular names. Thanks for your answers.
Related
This issue happens for me on Backpack v5 and Laravel 8 (although I do reproduce it on Laravel 9 as well).
My issue happens when I have a setup similar to this one : https://backpackforlaravel.com/docs/5.x/crud-fields#manage-related-entries-in-the-same-form-create-update-delete
Just to clarify here:
Two models related by a 1-n relationship
Those models override their $primaryKey attribute (as their primary key is not "id")
the "parent" models CRUD that has a 'type' => 'relationship' with 'subfields' to add children through a "repeatable" type field
This is the error I get (with the Monsters and Stories example):
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'id_story' in 'where clause'
select * from `monsters` where `monsters`.`story_id` = 5 and `monsters`.`story_id` is not null and (`id_story` is null) limit 1
The stack trace leads me to vendor\backpack\crud\src\app\Library\CrudPanel\Traits\Create.php:310
Here is how I reproduced it on the Backpack demo projet:
Install demo project following instructions here :https://backpackforlaravel.com/docs/4.1/demo#demo-installation
Rename monsters primary key in table to id_monster and stories primary key to id_story
Add the $primaryKey overrides on corresponding models like so:
protected $primaryKey = 'id_monster'; // In Monster.php
protected $primaryKey = 'id_story'; // In Story.php
Add correct "foreignKey" parameters to relation method like so:
// In Story.php
public function monsters()
{
return $this->hasMany(\App\Models\Monster::class, 'story_id');
}
// In Monster.php
public function story()
{
return $this->belongsTo(\App\Models\Story::class, 'story_id');
}
Now add a story with a monster through the Crud panel and you should reproduce the error.
I'm thinking I'm probably missing something but I just can't figure it out. I'm pretty sure the relations are properly defined and I'm wondering if it's not a bug in Backpack.
Thanks for your help !
UPDATE
This is indeed an issue that has been reported here
I'm seeing that you are using "story_id" in both relations (Story.php and Monster.php).
In Story.php you should use :
public function monsters()
{
return $this->hasMany(\App\Models\Monster::class, 'story_id');
}
And In Monster.php you should use :
public function story()
{
return $this->belongsTo(\App\Models\Story::class, 'monster_id');
}
Also be careful that when you are trying to set relationships in migrations and in models, you are setting correct foreign keys both in migration and models.
i have a model:
<?php
namespace App\Models;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
class MultiProductVariantPivot extends Model
{
//use HasFactory;
protected $table = "multi_product_variant_pivot";
/**
* The attributes that are mass assignable.
*
* #var array
*/
protected $fillable = [
'multi_product_id',
'variant_id',
'decision_tree',
'hashed_decision_tree'
];
}
I have a query:
$variant_decision_trees = MultiProductVariantPivot::where('multi_product_id', $multi_product_id)->get();
I have an error:
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'products.multi_product_variant_pivot' in 'where clause' (SQL: select * from `products` where `products`.`multi_product_variant_pivot` = 1 and `products`.`multi_product_variant_pivot` is not null)
Question: Could someone explain to me why Laravel is pointing to the 'products' table (a real table i have) and not the explicitly defined one? How do i stop Laravel overriding my decisions with impunity? Is there a terminal update command that i should have run to refresh something?
EDIT:
I have found another interesting thing, if i change the column name in the where() to "multi_product_id_test" instead of "multi_product_id" it will reference the correct table..
the new error given:
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'multi_product_id_test' in 'where clause' (SQL: select * from `multi_product_variant_pivot` where `multi_product_id_test` = 1)
Thus, the column selection in the where() is affecting the table selection.. anyone care to explain how to avoid this? also it seems to have added an extra "is not null" clause in the first query, there is defiantly something weird going on.
EDIT 2:
If I change my table name to anything wrong like mproduct_variant it uses the proper query, if I change it to match an existing table it does the wrong query.. Laravel is trying its hardest to make me not be productive, I'm quite impressed.
EDIT 3:
if i change the table name in my model to:
protected $table = "multi_product_variant";
the error i get is:
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'products.multi_product_variant_pivot' in 'where clause' (SQL: select * from `products` where `products`.`multi_product_variant_pivot` = 1 and `products`.`multi_product_variant_pivot` is not null)
as can be seen its using products.multi_product_variant_pivot instead of multi_product_variant. could someone explain this behavior? it seems to be caching my old table name? very strange.
That's because you are naming your model with "Pivot" suffix, which is interfering with Laravel's many-to-many relationship system and not the best practice. What you can do is "force" Laravel by telling it which table to use:
$variant_decision_trees = MultiProductVariantPivot
::where(`multi_product_variant_pivot.multi_product_id`, $multi_product_id)->get();
That's the possibility that I can think of, it may not be the root tho. And for the love of god. Follow the convention if you can.
okayy so here it is, i had a model called MultiProduct with a function to relate the variants of the product like so:
public function variants(){
return $this->hasMany( 'App\Models\Product', 'multi_product_variant_pivot');
}
so what was happening was my MultiProductVariant model was being translated into activating the variants() function from the MultiProduct model. I changed it to be:
public function products(){
return $this->hasMany( 'App\Models\Product', 'multi_product_variant');
}
and now it works because its not being linked! Dont ask me why, I'm just a consumer of this framework. Crazy stuff.
I have a table organisations with a number of columns, namely id, name, created_at and updated_at.
In my Organisation model, I added a custom attribute by adding the following code in the model:
// Add custom attributes
protected $appends = [
'device_count',
];
and:
public function getDeviceCountAttribute()
{
// Count organisation's devices
$device_count = Device::where('organisation_id', '=', $this->id)->count();
return $device_count;
}
In my controller, I am trying to search (using the where clause) by the device_count attribute, but I'm getting an error since this is not a real column in my database table.
This is how I'm searching:
$organisations = Organisation::query();
$organisations = $organisations->where('device_count', '=', 0);
$organisations = $organisations->get();
This is the error:
[2020-10-14 12:29:27] local.ERROR: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'device_count' in 'field list'...
Is there an alternative to the where clause in order to search by device_count please?
You can't query against attributes like that, they only exist on the model and do not exist in the database. However, you don't need to create a getter for that.
Laravel has a withCount() method you can use instead of that attribute - which is the correct approach of obtaining relational counts.
So a query with that attribute would look like
$organisations = Organisation::withCount('devices')->get();
The resulting models will now have a device_count attribute on them, that you can use in your views.
Then in your query, to filter those records that has at least a certain relational count, you can do
$organisations = Organisation::has('devices', '=', 0)->get();
Since you're looking for those that do not have any relation, you can replace it with doesntHave(). The above snippet is included to show how you can query against a specific set of relational counts.
To query only those that don't have any related devices, simply do
$organisations = Organisation::doesntHave('devices')->get();
This assumes that you have defined a devices relation on your Organisation class.
public function devices() {
return $this->hasMany(App\Models\Device::class); // Or App\Device::class if your models are not in the Models namespace/directory
}
The approaches above are the Laravel-way of doing it - and you should therefor remove your getDeviceCountAttribute() method and the corresponding device_count from $appends.
As per your requirement you want to get those Organisations which doesnot have any devices
For that, you need to use doesntHave method.
Make a relationship in the Organisation model.
public function devices() {
return $this->hasMany('App\Models\Device','organisation_id','id');
}
Now call the mothed in controller/
$organisations = Organisation::doesntHave('devices')->get();
it will return you those organisations which devices are not exists.
I want to get the count of the elements of materials count.
SubCategory:
public function materials(){
return $this->hasMany('App\Material');
}
Materials:
public function subcategories(){
$this->belongsTo('App\SubCategory','SubCategoria_id');
}
I want to get the count of the elements that have the subcategory_id
'quantidade' => $subcategory->material->count()
I'm getting error in 1054 Unknown column 'material.subcategory_id'
You should use the relationship to count. This will count the items using the DB. You should use the function like this:
'quantidade' => $subcategory->materials()->count()
And in the model, you have to inform the id in hasMany too:
public function materials(){
return $this->hasMany('App\Material' ,'SubCategoria_id');
}
You should also notice that it would be better if you name yours classes and variables according to Laravel patterns.
Does your material table have a subcategory_id column? This error could indicate it doesn't exist, therefore it's failing when you try the relationship.
As long as the column exists, the relationship should be valid and you should be able to count the results.
Since you're using a custom foreign key, you need to specify it. So, change the relation to:
public function materials()
{
return $this->hasMany('App\Material', 'SubCategoria_id');
}
And then use the proper relationship name:
$subcategory->materials()->count()
So, going into the problem straight away. someone told me that we dont need to make a pivot table if we only want to have ids of the table. laravel can itself handle this situation. I dont know how this works. I have a table community and another table idea. relation is like this;
One community can contain many ideas and an idea can be found in many
communities.
Relation in idea Model:
public function community() {
return $this->belongsToMany('App\Community')->withTimestamps();
}
Relation in community Model:
public function idea() {
return $this->belongsToMany('App\idea');
}
Now i want to fetch all the records related to a single community to show on its page Let's say the community is Arts.
Here is Controller function:
public function showCommunities($id) {
$community = Community::findOrFail($id)->community()->get();
return view('publicPages.ideas_in_community', compact('community'));
}
When i attach ->community()->get() to the Community::findOrFail($id) Then it throws the error
SQLSTATE[42S02]: Base table or view not found laravel
Any help would be appreciated.
Edit:
Logically, this piece of code Community::findOrFail($id)->community()->get() should be like this Community::findOrFail($id)->idea()->get(). Now it is true but it has little issue. it throws an error
Fatal error: Class 'App\idea' not found
The way you define the many-to-many relation looks ok - I'd just call them communities() and ideas(), as they'll return a collection of objects, not a single object.
Make sure you use correct class names - I can see you refering to your model classes using different case - see App\Community and App\idea.
In order to find related models, Eloquent will look for matching rows in the pivot table - in your case it should be named community_idea and have 3 fields: community_id, idea_id and autoincrement primary key id.
With that in place, you should be able to get all ideas linked to given community with:
$ideas = Community::findOrFail($communityId)->ideas;
If you need communities linked to given idea, just do:
$communities = Idea::findOrFail($ideaId)->communities;
You can read more about how to use many-to-many relationships here: https://laravel.com/docs/5.1/eloquent-relationships#many-to-many
someone told me that we dont need to make a pivot table if we only want to have ids of the table
The above is not true (unless I've just misunderstood).
For a many-to-many (belongsToMany) their must be the two related table and then an intermediate (pivot) table. The intermediate table will contain the primary key for table 1 and the primary key for table 2.
In laravel, the convention for naming tables is plural for your main tables i.e. Community = 'communities' and Idea = 'ideas'. The pivot table name will be derived from the alphabetical order of the related model names i.e.
community_idea.
Now, if you don't want/can't to follow these conventions that's absolutely fine. For more information you can refer to the documentation: https://laravel.com/docs/5.2/eloquent-relationships#many-to-many
Once you're happy that you have the necessary tables with the necessary fields you can access the relationship by:
$ideas = $community->ideas()->get();
//or
$ideas = $community->ideas;
So you controller would look something like:
public function showCommunities($id)
{
$community = Community::findOrFail($id);
//The below isn't necessary as you're passing the Model to a view
// but it's good for self documentation
$community->load('ideas');
return view('publicPages.ideas_in_community', compact('community'));
}
Alternatively, you could add the ideas to the array of data passed to the view to be a bit more verbose:
public function showCommunities($id)
{
$community = Community::findOrFail($id);
$ideas = $community->ideas
return view('publicPages.ideas_in_community', compact('community', 'ideas));
}
Hope this helps!
UPDATE
I would imagine the reason that you're receiving the App\idea not found is because the model names don't match. It's good practice (and in certain environments essential) to Capitalise you class names so make sure of the following:
Your class name is Idea and it's file is called Idea.php
The class has it's namespace declared i.e. namespace App;
If you've added a new class and it's not being found you might need to run composer dump-autoload from the command line to update the autoloader.