I'm sure this may be a simple solution, but I can't seem to work it out.
I am trying to use Laravel's where() clause to build an array of $courses that belong to each $student. I cycle through each $student and filter the $courseRecords to find matching courses based on their StudentCode.
Here is my sample code snippet:
// Cycle through the students and add their relevant course details
foreach( $students as $student ) {
// Find matching courses to the student
$courses = $courseRecords->where( 'StudentId', $student->StudentCode );
// Add the course array to the student record
$student->Courses = $courses;
}
However, the result I get, gives me each student's course, but with a leading index number (as shown below in random results):
I can't seem to work out why this is happening. The first entry (Id 0) is the result I am expecting, but for some reason, every other result seems to give me the matching index number of $courseRecord.
I have tried using $courses->all(); and $courses->toArray(); but this doesn't make any difference. From the Laravel documentation (that I have read), it doesn't mention this behaviour which makes me think I have something incorrect.
$students and $courseRecords are both a collection.
Use values():
$courses = $courseRecords->where('StudentId', $student->StudentCode)->values();
Related
I have a challenge that if I want to sort the records when getting using Laravel's ORM based on a list of IDs, how should I do it?!!!!!!!
I mean :
Suppose we have a table called users, which contains 100 records and each record has a unique ID.
We also have an array of IDs.
$ids = [4,1,2,3]
Now I want to get the list of users, but only the users who are first in the ids array and secondly according to the same order as they are listed in this array.
User::whereIn('id' , $Ids)->sortBy('id',$ids)->get();
Can you think of a solution to do this?
User::whereIn('id' , $Ids)->sortBy('id',$ids)->get();
The collections sortBy() function can take a custom call back this way:
$users = User::whereIn('id', $Ids)->get()
->sortBy(function($user, $key) use($ids) {
return array_search($user->id, $ids);
});
This will sort your collection according to the given array.
You can also reference the docs for more information.
Note that the sortBy() function must act upon a collection, which means that the get() function must come before it.
We are developing an API with LUMEN.
Today we had a confused problem with getting the collection of our "TimeLog"-model.
We just wanted to get all time logs with additional informationen from the board model and task model.
In one row of time log we had a board_id and a task_id. It is a 1:1 relation on both.
This was our first code for getting the whole data. This took a lot of time and sometimes we got a timeout:
BillingController.php
public function byYear() {
$timeLog = TimeLog::get();
$resp = array();
foreach($timeLog->toArray() as $key => $value) {
if(($timeLog[$key]->board_id && $timeLog[$key]->task_id) > 0 ) {
array_push($resp, array(
'board_title' => isset($timeLog[$key]->board->title) ? $timeLog[$key]->board->title : null,
'task_title' => isset($timeLog[$key]->task->title) ? $timeLog[$key]->task->title : null,
'id' => $timeLog[$key]->id
));
}
}
return response()->json($resp);
}
The TimeLog.php where the relation has been made.
public function board()
{
return $this->belongsTo('App\Board', 'board_id', 'id');
}
public function task()
{
return $this->belongsTo('App\Task', 'task_id', 'id');
}
Our new way is like this:
BillingController.php
public function byYear() {
$timeLog = TimeLog::
join('oc_boards', 'oc_boards.id', '=', 'oc_time_logs.board_id')
->join('oc_tasks', 'oc_tasks.id', '=', 'oc_time_logs.task_id')
->join('oc_users', 'oc_users.id', '=', 'oc_time_logs.user_id')
->select('oc_boards.title AS board_title', 'oc_tasks.title AS task_title','oc_time_logs.id','oc_time_logs.time_used_sec','oc_users.id AS user_id')
->getQuery()
->get();
return response()->json($timeLog);
}
We deleted the relation in TimeLog.php, cause we don't need it anymore. Now we have a load time about 1 sec, which is fine!
There are about 20k entries in the time log table.
My questions are:
Why is the first method out of range (what causes the timeout?)
What does getQuery(); exactly do?
If you need more information just ask me.
--First Question--
One of the issues you might be facing is having all those huge amount of data in memory, i.e:
$timeLog = TimeLog::get();
This is already enormous. Then when you are trying to convert the collection to array:
There is a loop through the collection.
Using the $timeLog->toArray() while initializing the loop based on my understanding is not efficient (I might not be entirely correct about this though)
Thousands of queries are made to retrieve the related models
So what I would propose are five methods (one which saves you from hundreds of query), and the last which is efficient in returning the result as customized:
Since you have many data, then chunk the result ref: Laravel chunk so you have this instead:
$timeLog = TimeLog::chunk(1000, function($logs){
foreach ($logs as $log) {
// Do the stuff here
}
});
Other way is using cursor (runs only one query where the conditions match) the internal operation of cursor as understood is using Generators.
foreach (TimeLog::where([['board_id','>',0],['task_id', '>', 0]])->cursor() as $timelog) {
//do the other stuffs here
}
This looks like the first but instead you have already narrowed your query down to what you need:
TimeLog::where([['board_id','>',0],['task_id', '>', 0]])->get()
Eager Loading would already present the relationship you need on the fly but might lead to more data in memory too. So possibly the chunk method would make things more easier to manage (even though you eagerload related models)
TimeLog::with(['board','task'], function ($query) {
$query->where([['board_id','>',0],['task_id', '>', 0]]);
}])->get();
You can simply use Transformer
With transformer, you can load related model, in elegant, clean and more controlled methods even if the size is huge, and one greater benefit is you can transform the result without having to worry about how to loop round it
You can simply refer to this answer in order to perform a simple use of it. However incase you don't need to transform your response then you can take other options.
Although this might not entirely solve the problem, but because the main issues you face is based on memory management, so the above methods should be useful.
--Second question--
Based on Laravel API here You could see that:
It simply returns the underlying query builder instance. To my observation, it is not needed based on your example.
UPDATE
For question 1, since it seems you want to simply return the result as response, truthfully, its more efficient to paginate this result. Laravel offers pagination The easiest of which is SimplePaginate which is good. The only thing is that it makes some few more queries on the database, but keeps a check on the last index; I guess it uses cursor as well but not sure. I guess finally this might be more ideal, having:
return TimeLog::paginate(1000);
I have faced a similar problem. The main issue here is that Elloquent is really slow doing massive task cause it fetch all the results at the same time so the short answer would be to fetch it row by row using PDO fetch.
Short example:
$db = DB::connection()->getPdo();
$query_sql = TimeLog::join('oc_boards', 'oc_boards.id', '=', 'oc_time_logs.board_id')
->join('oc_tasks', 'oc_tasks.id', '=', 'oc_time_logs.task_id')
->join('oc_users', 'oc_users.id', '=', 'oc_time_logs.user_id')
->select('oc_boards.title AS board_title', 'oc_tasks.title AS task_title','oc_time_logs.id','oc_time_logs.time_used_sec','oc_users.id AS user_id')
->toSql();
$query = $db->prepare($query->sql);
$query->execute();
$logs = array();
while ($log = $query->fetch()) {
$log_filled = new TimeLog();
//fill your model and push it into an array to parse it to json in future
array_push($logs,$log_filled);
}
return response()->json($logs);
I have a table called post that HAS MANY comments I need to sort the list of post by how many comments there are in a post.
In fuelPHP, is there a way to do this in ORM? I want to make sure before I do it manually.
Thanks.
Short answer for this: No, there's not. It is not possible for the ORM to sort for you like that without doing it manually.
To work around it:
// construct an array with post-id => comment-count
$ordered = array();
foreach($posts as $id => $post)
{
$ordered[$id] = count($post->comments);
}
// order the array, largest count first
arsort($ordered, SORT_NUMERIC);
// merge the posts in, maintaining order
$ordered = array_replace($ordered, $posts);
This uses takes advantage of the feature that array_replace will maintain the key order of the first array.
I am new to laravel and confused about some query methods.
find($id) is useful and returns a nice array, but sometimes I need to select by other fields rather than id.
The Laravel document said I could use where('field', '=', 'value') and return a bunch of data, which is fine.
What I can't understand is why I need to add ->first() every time, even if I am pretty sure there is only one single row matches the query.
It goes like this:
$query->where(..)->orderBy(..)->limit(..) etc.
// you can chain the methods as you like, and finally you need one of:
->get($columns); // returns Eloquent Collection of Models or array of stdObjects
->first($columns); // returns single row (Eloquent Model or stdClass)
->find($id); // returns single row (Eloquent Model or stdClass)
->find($ids); // returns Eloquent Collection
// those are examples, there are many more like firstOrFail, findMany etc, check the api
$columns is an array of fields to retrieve, default array('*')
$id is a single primary key value
$ids is an array of PKs, this works in find method only for Eloquent Builder
// or aggregate functions:
->count()
->avg()
->aggregate()
// just examples here too
So the method depends on what you want to retrieve (array/collection or single object)
Also the return objects depend on the builder you are using (Eloquent Builder or Query Builder):
User::get(); // Eloquent Colleciton
DB::table('users')->get(); // array of stdObjects
even if I am pretty sure there is only one single row matches the query.
Well Laravel cant read your mind - so you need to tell it what you want to do.
You can do either
User::where('field', '=', 'value')->get()
Which will return all objects that match that search. Sometimes it might be one, but sometimes it might be 2 or 3...
If you are sure there is only one (or you only want the first) you can do
User::where('field', '=', 'value')->first()
get() returns an array of objects (multiple rows)
while
first() returns a single object (a row)
You can of course use get() when you know it will return only one row, but you need to keep that in mind when addressing the result:
using get()
$rez = \DB::table('table')->where('sec_id','=','5')->get();
//will return one row in an array with one item, but will be addressed as:
$myfieldvalue = $rez[0]->fieldname;
using first()
$rez = \DB::table('table')->where('sec_id','=','5')->first();
// will also return one row but without the array, so
$myfieldvalue = $rez->fieldname;
So it depends on how you want to access the result of the query: as an object or as an array, and also depends on what "you know" the query will return.
first() is the equivalent of LIMIT 1 at the end of your SELECT statement. Even if your query would return multiple rows, if you use first() it will only return the first row
I have two models: Plans and PlanDetails.
Relationship is: PlanDetails hasMany Plans. Plans belongTo PlanDetails.
In the PlanDetails view.ctp, I am pulling in related Plans.
I am trying to sort the Plans by ANY field (I've tried them all), and I cannot get it working. I assume I am overlooking something very simple.
Here is my base code:
PlanDetail >> view.ctp:
...foreach ($planDetail['Plan'] as $plan_edit) :
$class = null;
if ($i++ % 2 == 0) {
$class = ' class="altrow"';
}...
<?php echo $this->Paginator->sort('Plan ID', 'Plan.id'); ?>...
...<?php echo $plan_edit['id']; ?>
plan_details_controller.php:
...function view($id = null) {
if (!$id) {
$this->Session->setFlash(__('Invalid plan detail', true));
$this->redirect(array('action' => 'index'));
}
$this->PlanDetail->recursive = 2; // To run the editable form deeper.
$this->set('planDetail', $this->PlanDetail->read(null, $id));
$this->set('plan', $this->paginate('Plan'));
}...
I should add, no errors are being thrown and the sort() arrows on the ID field are showing as expected, but the sort order DOES not change when clicked either way.
Sorry, I'm not able to comment on the question itself, but I've noticed that in your action, you set planDetail to be the PlanDetail record you read (with recursive set to 2), and then you set plan to be the result of the paginate call.
Then, in your view template, you're iterating over $planDetail's contained Plan association, like this:
foreach ($planDetail['Plan'] as $plan_edit):
But in order to get the sorting and pagination done, you need to be displaying the results of the paginate call i.e. iterate over the records contained in $plan.
Do a debug($plan) in your view template to see what results you get there and to see if the records' ordering changes when you sort by different fields.
Also, perhaps you're using syntax I'm not aware of, but if you simply call $this->paginate('Plan') in your controller, I don't know that you're going to get only the related Plan records for your particular PlanDetail record. (There's nothing tying the $id passed into your view action with the Plan records.) You might need to add some conditions to the paginate call, like so:
$this->paginate['Plan'] = array('conditions' => array('Plan.plan_detail_id' => $id));
$this->set('plans', $this->paginate('Plan'));
Here is what I did to solve this. Based on some helpful direction from johnp & tokes.
plan_details/view.ctp:
...$i = 0;
foreach ($plan as $plan_edit) : // note $plan here.
}...
In my plan_details_controller.php view action:
$conditions = array("Plan.plan_detail_id" => "$id");
$this->set('plan', $this->paginate('Plan', $conditions)); // note "plan" in the first argument of set (this is required to pass the results back to the view). Also. The $condition is set to return ONLY plans that match the plan_detail_id of id (on the plan_details table).
And in my view, in order to get my results (because I changed the array name), I had to change the way I was getting the values to:
$plan_edit['Plan']['modified'] // note I placed ['Plan'] in front of these calls as the array called for this to get the data...
Well until the next problem! SOLVED.