I have this query in Laravel (5.3):
$menu_categories = DB::table('categories')->get();
It returns the categories from the database as expected. However, if I split it (so that I can add other parameters):
$menu_categories = DB::table('categories');
$menu_categories->get();
It returns a massive collection that starts like this:
Illuminate\Database\Query\Builder Object
(
[connection:protected] => Illuminate\Database\MySqlConnection Object
(
[pdo:protected] => PDO Object
(
)
[readPdo:protected] =>
[reconnector:protected] => Closure Object
(
[this] => Illuminate\Database\DatabaseManager Object...
What is happening here? I've searched for a while and can't find anything on this - although I admit I'm not sure what to search for. Note that I am NOT adding any additional parameters when it has the weird return collection - I saw the weird return initially with extra params (orderBy and whereIn) but even after removing those it still returns this weirdness.
The "non split" line is creating a query object for the categories table, calling get() on the query object and assigning the results of get() to the $menu_categories variable.
In the split version, the first line creates a query object for the categories table and sets it in the $menu_categories variable.
In the second line, calling get() on $menu_categories doesn't actually mutate the variable. Instead it returns the collection that you're looking for but it's not being assigned to anything. This is why you just see this massive object when you dump it.
The correct 2 line version would look something like this:
$query_object = DB:table('categories');
$menu_categories = $query_object->get();
Related
This eloquent collection provides this result:
$id = Model::where('s_id', $s_id)->pluck('l_id');
print_r($id)
Illuminate\Support\Collection Object
(
[items:protected] => Array
(
[0] => 31242682774
)
)
How do I return only the "31242682774" value as a string and not a collection?
EDIT ANSWER:
All I had to do is:
$id = Model::where('s_id', $s_id)->pluck('l_id')->first();
Any better options?
If you only need a single value, not multiple values, pluck isn't what you want. There is a method called value on Query Builder that returns a single value:
Model::where('s_id', $s_id)->value('l_id');
Laravel 6.x Docs - Query Builder - Retrieving Results - Retrieving A Single Row / Column From A Table value
It compares to when it the process you wanna do it. On the query execution or after. The most common approach would probably be.
$id = Model::where('s_id', $s_id)->first()->l_id;
This will execute after, meaning the query builder will fetch all columns in the row. In general in Laravel you don't that often work with strings and or other abstractions than your model. Model::where('s_id', $s_id)->first() will return your model and select the l_id property on it.
The approach you chosen is the database way, you only select the l_id and return it as a collection and select the first item from there. This is thou a very performance efficient way of doing it since the database does all the work and is very quick at it.
$id = Model::where('s_id', $s_id)->pluck('l_id')->first();
The reason why it is a collection, it is mainly made for selecting multiple id's, so if you query returned multiple rows multiple ids would be returned. Here you can see an example of pluck in conditional queries, where it is most often used.
$teamIds = Team::where('type', 'admin')->pluck('id');
$adminUsers = User::where('team_id', $teamIds)->get();
Your solution is perfect for what you need, just trying to bring clarity on why and a example of how it is often used.
I am trying to get the value of a single column using Eloquent:
MyModel::where('field', 'foo')->get(['id']); // returns [{"id":1}]
MyModel::where('field', 'foo')->select('id')->first() // returns {"id":1}
However, I am getting anything but the value 1. How can get that 1?
NOTE: It is possible that the record with field of foo does not exist in the table!
EDIT
I am ideally looking for a single statement that either returns the value (e.g. 1) or fails with a '' or null or other. To give you some more context, this is actually used in Validator::make in one of the rules:
'input' => 'exists:table,some_field,id,' . my_query_above...
EDIT 2
Using Adiasz's answer, I found that MyModel::where('field', 'foo')->value('id') does exactly what I need: returns an integer value or an empty string (when failed).
Laravel is intuitive framework... if you want value just call value() method.
MyModel::find(PK)->value('id');
MyModel::where('field', 'foo')->first()->value('id');
You're using the Eloquent query builder, so by default, it'll return an Eloquent model with only the value you wish.
The method you're looking for is pluck() which exists in the normal query builder (of which the Eloquent one extends) so your code should look as follows:
MyModel::where('field', 'foo')->pluck('id'); // returns [1]
The value() method that is being used in the other answers is an Eloquent model method. Using that means that the framework queries the database, hydrates the model and then returns only that value. You can save yourself a few keystrokes and few CPU cycles by using pluck() and have it handled simply in one query.
So I have the following where clause where I am searching the name "Gold" inside of my tier table.
$tier = Tier::where(['name' => 'Gold'])->get(['id']);
dd($tier);
When I do the above the "id" is listed inside of the attributes but when I do as below it gives me
Undefined property: Illuminate\Database\Eloquent\Collection::$id
dd($tier->id);
All I want is to get the Id of the record where the name is "Gold".
To get actual model you should use first() instead of get(). Because there are potentially multiple rows that match get() will return a collection.
$tier = Tier::where(['name' => 'Gold'])->first(['id']);
dd($tier->id);
If you really need only the id there's even a simpler function to that, pluck().
It will get one attribute from the first result:
$id = Tier::where(['name' => 'Gold'])->pluck('id');
LINQ newbie here.
I have a long LINQ query, called it MYLONGQUERY, that returns a collection of certain class instances. If the list is not empty, I want to return a property (MYPROPERTY) of the first instance; otherwise it returns some default value (DEFAULTPROPERTY). So the query looks like this
(0 != MYLONGQUERY.count()) ? MYLONGQUERY.FirstOrDefault().MYPROPERTY: DEFAULTPROPERTY
This works fine. However, I don't like the fact that I have to repeat MYLONGQUERY before and after "?". I have been trying Let and Into, but have not been able to get those to work. And it has to be Method Syntax, not Query Syntax. Suggestions? Appreciate it.
You have to select the property first, then you can specify the default-value with DefaultIfEmpty:
var prop = MYLONGQUERY
.Select(x => x.MYPROPERTY)
.DefaultIfEmpty(DEFAULTPROPERTY) // new default-value
.First(); // never exception
I am new to laravel and confused about some query methods.
find($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