Hi I was able to get the values from two tables, now I want this two values to be subtracted. How can i do it here in laravel?
public function displayBalance()
{
$results= DB::table('accountspayable')
->selectRaw('sum(accountspayable.amount) as sum')
->where('accountspayable.regnum','=','15459')
->get();
$subjects= DB::table('pay')
->selectRaw('sum(pay.amount) as sum')
->join('accountspayable','pay.accountno','=','accountspayable.accountno')
->where('accountspayable.regnum','=','15459')
->get();
return View::make('users.Balance')->with(array('results'=>$results,'subjects'=>$subjects));
}
Try it this way:
public function displayBalance()
{
$results = DB::table('accountspayable')->
where('regnum'. '='. '15459')->
sum('amount');
$subjects = DB::table('pay')->
join('accountspayable','pay.accountno','=','accountspayable.accountno')->
where('accountspayable.regnum','=','15459')->
sum('pay.amount');
return View::make('users.Balance', compact('results', 'subjects'));
}
You were probably getting collections of 1 record having 1 attribute (sum). And that's the only thing you basically need. So you can use aggregate functions directly in your query builder to get the SUM values.
Also I used "compact" to assign the values you just retrieved to the view. This is not necessary but saves some code and is easier to read.
Related
I got two tables. Both have a relationship to each other. I´m trying to query both to get the matching results. This results get checked if they also have an column which matches with a parameter value.
I´m trying it with a scope and it work. I only need one column from the second table and I´m trying to use it as column in my first table when I got my result.
So the code works and I got an result but I´m trying to filter to select only one column from the second table.
My code look like that.
My controller:
public function test()
{
$UID='LQuupgYvnuVzbEoguY4TF8bnHUU2';
$event=Events::withState($UID)->get();
echo $event;
}
My model scope function:
public function scopeWithState($query,$UID){
return $query->with(['EventLiked' => function($query) use($UID) {
$query
->where('EventLiked.UID', $UID)
;
}]);
}
My hasMany relationship function:
public function EventLiked()
{
return $this->hasMany(EventLiked::class,'EID','ID')->select('State','UID','EID');
}
I would go for specifying columns inside closure.
New scope:
public function scopeWithState($query,$UID){
return $query->with(['EventLiked' => function($query) use($UID) {
$query
->where('EventLiked.UID', $UID)
->select('State');
}]);
}
Calling scope:
$event=Events::withState($UID)->get();
You're not getting expected results because Laravel splits it into 2 queries:
First, for selecting events.
Then it plucks EID
Second, when it looks for EventLiked where matching ID's is found (from second step) and loads as relationships.
So you want to change select statement only in 2nd query. Not in a first one
I am using Laravel 5.4,
How to sort twice with two columns?
For example:
ArticleController.php
public function index()
{
$articles = Auth::user()->articles->sortByDesc('updated_at')->sortByDesc('status');
return view('index', compact('articles'));
}
I use sortByDesc() twice,but the result does not follow the rules,what should I do?
update:
User.php
public function articles()
{
return $this->hasMany('App\Article');
}
You shouldn't sort on collection but you should get sorted results from database like this:
$articles = Auth::user()->articles()
->orderBy('updated_at', 'DESC')
->orderBy('status','DESC')
->get();
To explain a bit more - in your code you got all results from database (in random order) and then tried to sort all the results.
In code I presented you sort results in database so you can easily sort on mutliple columns.
Notice difference in my code - instead of ->articles I used ->articles() and added ->get() at the end to get results.
I'm trying to retrieve single column from my table grades.
For that I have used following code in my controller:
public function verify($id,$sid)
{
$grade=Grade::all('annual')->whereLoose('id',$id);
return $grade;
}
Where, annual is column name. But it is returning empty set of array [].
all() takes a list of columns to load from the database. In your case, you're fetching only one column called annual, therefore filtering on id later on does not return results. Replace your code with the following and it should work:
$grade = Grade::all('id', 'annual')->whereLoose('id', $id);
Keep in mind that it will return a collection of objects, not a single object.
NOTE: you're always loading all Grade objects from the database which is not efficient and not necessary. You can simply fetch object with given id with the following code:
$grade = Grade::find($id); // fetch all columns
$grade = Grade::find($id, ['id', 'annual']); // fetch only selected columns
The code you are using is loading all rows from the grades table and filtering them in code. It is better to let your query do the filter work.
For the columns part, you can add the columns you need to the first() function of the query, like so:
public function verify($id,$sid)
{
$grade = Grade::where('id', $id)->first(['annual']);
return $grade->annual;
}
I presently have 3 tables: Shows, Genres and Show_Genre (associates the two). I have a search form that submits a series of checkboxes with values into an array based on what genres they selected. Presently I want to associate the Shows table and the Genres table into a variable and run a query against it once for every genre checkbox selected. Then, once the selection is filtered, I can display the resulting Show objects that matched the users parameters.
My present setup is the following
public function searchShows(SearchRequest $request)
{
//$ShowsWithGenres give a collection inside a collection which I can't seem to even access its values without doing a bunch of ugly code using count() in a for loop
$ShowsWithGenres = Show::with('genres')->get();
$genres = $request->name;
if(isset($genres))
{
foreach($genres as $genre)
{
//iterate against the selection repeatedly reducing the number of results
}
}
}
Thanks.
You should use whereHas() and whereIn.
Perhaps something like this should do it:
$shows = Show::whereHas('genres', function($q) use($genre_ids)
{
$q->whereIn('id', $genre_ids);
})->get();
EDIT
Try this, however I'm unsure about the performance.
$query= Show::query();
foreach($genre_ids as $id){
$query->whereHas('genres', function($q) use($id)
{
$q->where('id', $id);
})
}
$shows = $query->get();
Using Eloquents whereHas() function you can query results based on the relation's data. http://laravel.com/docs/5.0/eloquent#querying-relations
public function searchShows(SearchRequest $request)
{
// Start a query (but don't execute it at this point as we may want to add more)
$query = Show::with('genres');
$genreNames = (array) $request->name;
// Check there are some genre names, if theres not any it'll cause an SQL syntax error
if (count($genreNames) > 0)
{
$query->whereHas('genres', function($subQuery) use ($genreNames)
{
$subQuery->whereIn('genre_name', $genreNames);
}
}
// Finally execute the query. $shows now contains only shows with the genres that the user has searched for, if they didn't search with any genres, then it contains all the results.
$shows = $query->get();
}
How to merge this two queries ?
$data = DB::table('category_to_news')
->where('category_to_news.name', ucwords($category))
->remember(1440)
->count();
and
$data = DB::table('category_to_news')
->where('category_to_news.name', ucwords($category))
->remember(1440)
->get();
So, as far as I understand from your comment, you simply want to get all records from the table category_to_news and you want to know how many records are in there, right?
MySQL's count is an aggregate functions, which means: It takes a set of values, performs a calculation and returns a single value. If you put it into your names-query, you get the same value in each record. I'm not sure if that has anything to do with 'optimization'.
As already said, you simply run your query as usual:
$data = DB::table('category_to_news')
->where('name', ucwords($category))
->remember(1440)
->get(['title']);
$data is now of type Illuminate\Support\Collection which provides handy functions for collections, and one them is count() (not to be confused with the above mentioned aggregate function - you're back in PHP again, not MySQL).
So $data->count() gives you the number of items in the collection (which pretty much is an array on steroids) without even hitting the database.
Hi DB class dont return collection object it give error "call member function on array" but eloquent return collection object. for above code we can use collect helper function to make it collection instance then use count and other collection methods https://laravel.com/docs/5.1/collections#available-methods .
$data = DB::table('category_to_news')
->where('name', ucwords($category))
->remember(1440)
->get();
$data = collect($data);
$data->count();
You my get it using:
$data = DB::table('category_to_news')
->where('name', ucwords($category))
->remember(1440)
->get();
To get the count, try this:
$data->count();
Why you are using DB::table(...), instead you may use Eloquent model like this, create the model in your models directory:
class CategoryToNews extends Eloquent {
protected $table = 'category_to_news';
protected $primaryKey = 'id'; // if different than id then change it here
}
Now, you may easily use:
$data = CategoryToNews::whereName(ucwords($category))->get();
To get the count, use:
$data->count();