I have user and news table and then a middle table called news_user, the middle table determines which news has been seen by the user. I can easily get objects that have been seen but, but now I need to show the user objects that have not been seen.
I did a workaround with putting all the seen news id in an array and look for news where id differs from the array. but I don't consider it as the healthiest solution.
This is what I did:
$seenNewses = DB::table('news_user')->where('user_id', Auth::id())
->pluck('news_id')->toArray();
$notSeenNewses = News::whereNotIn('id', $seenKeepers)
->orderBy('id', 'asc')->first();
Is there a way I can do this with a single query?
P.S: I have seen similar questions but they got little confused. Any answer is appreciated.
First in your News Model you need to make relationship like this
public function users()
{
return $this->belongsToMany(News::class,'news_user','news_id','user_id');
}
Below command will give you all the news which are not seen by any users yet
$notSeenNewses = News::doesntHave('users')->get();
If you want to put any condition then also check for
$notSeenNewses = News::whereDoesntHave('users', function ($query) {
$query->where('YOUR CONDITION');
})->get();
It's not tested but you can modify as per your need.
Related
If I have a Laravel 5.5 model called User that hasMany Posts and each Post hasMany Hits, is there an aggregate function I can call to get the total number of Hits for a User across all Posts, where the Hit was created in the last week?
It seems like there may be a clever way to do it besides doing something like
$hits = $user->posts()->hits()
and then looping over those hits to check created date.
In this case it seems like raw sql would be better, but I figured there may be an Eloquent way to handle a situation like this.
I think the right solution is just to use a HasManyThrough relationship to grab all the Hit rows, joined through the posts table.
So it'd look like this on the User model (roughly):
return $this->hasManyThrough(
Hit::class,
Post::class
// if you have non-standard key names you can specify them here-- see docs
);
Then when you have your User model you can just call $user->hits to get a collection of all the associated hits through all the user's Posts
You can add the code below to your Post model.
protected static function boot()
{
parent::boot();
static::addGlobalScope('hitCount', function ($builder) {
$builder->withCount('hits');
});
}
It automatically provides a field hits_count whenever you fetch a post.
$post = Post::first();
$hits = $post->hits_count; //Count hits that belongs to this post
You can read the documentation here to customize it to your need.
Set HasManyThrough relation in the User model:
public function hits()
{
return $this->hasManyThrough('App\Models\Hits','App\Models\Posts','user_id','post_id','id');
}
then you can do this:
$reults = $user->hits()->where('hits_table_name.created_at', '>=', Carbon::today()->subWeek())->count();
HasManyThrough Link
Use DB::enableQueryLog(); and DB::getQueryLog(); to see if executed SQL Query is correct;
I've found some query result really unexpected.
It's Laravel 5.2
We have following entity:
User with method:
public function roles() : BelongsToMany
{
return $this->belongsToMany(Role::class)->withPivot('timestamp');
}
Each User can have many roles, so we have also Role entity (but it doesn't matter much in my question) and pivot table user_role with timestamp field (and ids of course), because we hold information about time, when User achieved specific role.
I want to get all Users with theirs last assigned Role
When I create query (in User context in some repository):
$this->with(['roles' => function($query) {
$query->orderBy('timestamp', 'desc');
}])->all();
the result will contain Users with Roles entities inside itself ordered by timestamp - it's ok. But I want to retrieve only one last role inside each User entity not all ordered.
So...
$this->with(['roles' => function($query) {
$query->orderBy('timestamp', 'desc')->limit(1);
}])->all();
And then I retrieve Users but only User which achieved some Role for the very last time contains it! All the other Users have their roles field containing empty array.
Why ordering was performed on each Users relation separately, but when I added limit it behaved like a global limit for all.
It drives me crazy...
Thanks for advices.
EDIT
I've created lastRoles() method to get all Roles ordered desc. But all, retrieving one is impossible.
public function lastRoles() : BelongsToMany
{
return $this->BelongsToMany(Roles::class)->withPivot('timestamp')->latest('timestamp');
}
And for testing:
$users = (new User())->with('lastRoles')->get();
But now I must iterate over Users and invoke lastRoles() on each one:
foreach ($users as $user) {
var_dump($user->lastRoles()->get()->first()->name);
}
Then I retrieve names of latest Roles assigned to each User.
So... There is no way to do it in one query? This is the only way?
For this to work, you would need a helper function:
public function latestRole()
{
return $this->hasOne(Role::class)->withPivot('timestamp')->orderBy('timestamp', 'DESC');
}
And then:
$this->with('latestRole')->get();
Credits to this awesome article.
When you eager load a relationship with query constraint(s), the query will be run once to load all relationships, not each one individually. This is the expected behavior. Think about it, eager loading exists to turn many queries into one query in order to optimize performance. There is only one query executed, so your limit constraint will limit the entire result set, rather than on a per model basis.
To circumvent this, you could try creating another belongsToMany method that adds the desired limit constraint. The following code is untested:
public function lastRole() : BelongstoMany
{
return $this->belongsToMany(Role::class)
->withPivot('timestamp')
->orderBy('timestamp', 'desc')
->limit(1);
}
Assuming this works, you can then simply change the relationship method from roles to lastRole and remove your query constraint:
$this->with('lastRole')->all();
Here is the situation: I have 4 models.
Invoices
Creditors
Debtors
Timelines
These objects are related as such:
An invoice has a Creditor, a Debtor, and may have a Timeline.
A Debtor also may have a Timeline.
A Creditor has a Timeline.
I am trying to write the timeline() relationship on Invoice to take into account the order of priority of these objects. If the Debtor has a Timeline, it is used. Else, if the Invoice has a Timeline, it is used. Lastly, the Creditor's Timeline is used if neither of the above were found.
I have looked around quite a bit, and I am struggling to find a solution to this. In my head, it would be simple, though it is proving not so.
Approaches I have taken to no avail...
Putting a raw select statement into the relationship where the select will return the _rowid of the timeline desired:
return $this->hasOne('Timeline', '_rowid', 'SELECT ...')
Same idea, using DB::raw():
return $this->hasOne('Timeline', '_rowid', DB::raw('SELECT ...'))
Trying to load using selects and joins to the relationship query:
return $this->hasOne('Timeline', '_rowid', 'timeline_rowid')
->select('Timelines_Country.*')
->join(DB::raw('(select if(Debitor.timeline_rowid is not null, Debitor.timeline_rowid, if(Invoice.timeline_rowid is not null, Invoice.timeline_rowid, Creditor.timeline_rowid)) as timeline_rowid from Invoice join Debitor on Invoice.unique_string_cd = Debitor.unique_string_cd join Creditor on Creditor.id = Invoice.creditor_id where Debitor.timeline_rowid is not null and Invoice.timeline_rowid is not null) temp'), function($join){
$join->on('Timelines_Country._rowid', '=', 'temp.timeline_rowid');
})
->whereNotNull('temp.timeline_rowid');
The final solution seemed the closest, but it still included the standard relationship query of "WHERE IN (?,?,?)" where the list was the timeline_rowids from the collection of Invoices, which caused certain timelines to still not be found.
Thanks in advance for any help!
Ok. I guess I fundamentally misunderstood how relationships work. Because they are loaded after the model is already instantiated, the array for the wherein part of the relationship query is built from accessing attributes of the model. Once I discovered that, it was actually an easy fix.
I wrote this function, which returns the timeline_rowid based on the relationships:
public function getDerivedTimelineAttribute()
{
if ($this->debtor && $this->debtor->timeline_rowid)
{
return $this->debtor->timeline_rowid;
}
else if ($this->timeline_rowid)
{
return $this->timeline_rowid;
}
else if ($this->creditor->timeline_rowid)
{
return $this->creditor->timeline_rowid;
}
else
{
Log::Debug("can't find timeline", ['cdi' => $this->unique_string_cdi]);
return 0;
}
}
and then modified the relationship to read as:
public function timeline()
{
return $this->hasOne('Timeline', '_rowid', 'derivedTimeline');
}
I hope this helps someone else. Drove me nuts for a while figuring it out!
I have the following models in Eloquent: groups, threads, comments and users. I want to find all comments in a specific group from a specific user.
This is my current approach:
$group->threads->each(function ($thread) use ($user_id)
{
$user_comments = $thread->comments->filter(function ($comment) use ($user_id)
{
return $comment->owner_id == $id;
});
});
This looks ugly as hell, is probably slow as hell, and I just want to get rid of it. What is the fastest and most elegant way in Eloquent to get to my result set?
If a group hasMany threads, and a thread hasMany comments, you can add another relationship to group: group hasMany comments through threads.
On the group:
public function comments() {
return $this->hasManyThrough('Comment', 'Thread');
}
Now, you can get the comments in a group by $group->comments;
From here, you can tack on the requirement for the user:
$user_comments = $group->comments()->where('owner_id', $user_id)->get();
If you want, you can extract the where out into a scope on the Comment.
patricus solution pointed me in the right direction. I cross posted my question to the laracasts Forum and got a lot of help from Jarek Tkaczyk who also frequently visits this site.
hasManyThrough() for the Group model is the way to go:
public function comments()
{
return $this->hasManyThrough('ThreadComment', 'Thread');
}
There a couple of caveats, though:
Use the relation object instead of a collection ($group->comments(), NOT $group->comments)
If you use Laravel’s soft deletes you can’t just change the get() to a delete(), because you’ll get an ambiguity error for the column updated_at. You can’t prefix it either, it’s just how Eloquent works.
If you want to delete all comments from a specific user in a specific group you’ll have to do it a little bit differently:
$commentsToDelete = $group->comments()
->where('threads_comments.owner_id', $id)
->select('threads_comments.id')
->lists('id');
ThreadComment::whereIn('id', $commentsToDelete)->delete();
You basically fetch all relevant IDs in the first query and then batch delete them in a second one.
This may be a dupe but I've been trawling for some time looking for a proper answer to this and haven't found one yet.
So essentially all I want to do is join two tables and attach a where condition to the entire collection based on a field from the joined table.
So lets say I have two tables:
users:
-id
-name
-email
-password
-etc
user_addresses:
-address_line1
-address_line2
-town
-city
-etc
For the sake of argument (realising this may not be the best example) - lets assume a user can have multiple address entries. Now, laravel/eloquent gives us a nice way of wrapping up conditions on a collection in the form of scopes, so we'll use one of them to define the filter.
So, if I want to get all the users with an address in smallville, I may create a scope and relationships as follows:
Users.php (model)
class users extends Eloquent{
public function addresses(){
return $this->belongsToMany('Address');
}
public function scopeSmallvilleResidents($query){
return $query->join('user_addresses', function($join) {
$join->on('user.id', '=', 'user_addresses.user_id');
})->where('user_addresses.town', '=', 'Smallville');
}
}
This works but its a bit ugly and it messes up my eloquent objects, since I no longer have a nice dynamic attribute containing users addresses, everything is just crammed into the user object.
I have tried various other things to get this to work, for example using a closure on the relationship looked promising:
//this just filters at the point of attaching the relationship so will display all users but only pull in the address where it matches
User::with(array('Addresses' => function($query){
$query->where('town', '=', 'Smallville');
}));
//This doesnt work at all
User::with('Addresses')->where('user_addresses.town', '=', 'Smallville');
So is there an 'Eloquent' way of applying where clauses to relationships in a way that filters the main collection and keeps my eloquent objects in tact? Or have I like so many others been spoiled by the elegant syntax of Eloquent to the point where I'm asking too much?
Note: I am aware that you can usually get round this by defining relationships in the other direction (e.g. accessing the address table first) but this is not always ideal and not what i am asking.
Thanks in advance for any help.
At this point, there is no means by which you can filter primary model based on a constraint in the related models.
That means, you can't get only Users who have user_address.town = 'Smallwille' in one swipe.
Personally I hope that this will get implemented soon because I can see a lot of people asking for it (including myself here).
The current workaround is messy, but it works:
$products = array();
$categories = Category::where('type', 'fruit')->get();
foreach($categories as $category)
{
$products = array_merge($products, $category->products);
}
return $products;
As stated in the question there is a way to filter the adresses first and then use eager loading to load the related users object. As so:
$addressFilter = Addresses::with('Users')->where('town', $keyword)->first();
$users= $addressFilter->users;
of course bind with belongsTo in the model.
///* And in case anyone reading wants to also use pre-filtered Users data you can pass a closure to the 'with'
$usersFilter = Addresses::with(array('Users' => function($query) use ($keyword){
$query->where('somefield', $keyword);
}))->where('town', $keyword)->first();
$myUsers = $usersFilter->users;