I am using laravel
I want to change the value of a column according to a specific condition.
if a condition is satisfied in wherehas then change the value of specific column to 1 let's say.How could i do it.
if i can call a function in the model inside the wherehas function to change the value how could I do it ??
i can iterate the result set using a 2 for loops and change it, however I want to decrease the complexity by changing the value while retrieving the data
Course::with('stages','stages.levels')->whereHas('stages.levels', function($query)use ($levelsarray){
$query->wherenotIn('id', $levelsarray);
here I want to change a column value in table levels
})->first();
Here is a general way,
Assuming you have Three models, Course, Stage, Level
When you are retrieving data from Level model, add an accessor,
For more info click here.
Eg:
On Level.php model,
public function getColumnNameAttribute($value) // replace ColumnName with column name
{
//write application logic here.
return $value;
}
Related
quite a noob in Laravel and Livewire, I guess if there is a better way to accomplish what I have here:
I have some checkboxes in a Livewire view that allow the user to dynamically choose how to filter the data being shown in a HTML table.
On the controller I have an eloquent query that retrieves a subset of the records in the db whenever a checkbox changes state.
Like this (I tried to simplify the structure):
$filtered_items = Item::select('item_color', 'item_quantity', 'item_value')
->whereIn('item_color', [ /* array controlled by checkboxes values in view */ ])
->get();
I need to also show the sums of some columns for that specific filter setup.
As I don't want to make new queries, I try to work on the already available collection with a ->sum() for each column I want to sum:
$sums['item_quantity'] = $filtered_items->sum('item_quantity');
$sums['item_value'] = $filtered_items->sum('item_value');
It works as intended, as I have an array with the sums, but I was wondering if there is a better way to do this, or even write a function to get more columns sum at once, maybe passing an array.
Thanks for any idea or link!
Here is an example of a single query for all sums (two in this example)
$filtered_items = \DB::table('items')
->selectRaw('SUM(item_quantity) as sum_quantity, SUM(item_value) as sum_value')
->whereIn('item_color', [ /* array controlled by checkboxes values in view */ ])
->first();
The advantage is that it will return one entry/row instead of a collection of all the items which is way faster.
I have a query that needs to use a custom function like is showed below.
The problem is that one of the parameters is a value of another field from the same query.
The function is "calcula_distancia" and "$ofps[0]->latitude" and "$ofps[0]->longitude" are fields from a previus query.
The function needs 4 parameters and the last two are field from $necps that is beeing selected, but I can not retrieve the value from it using just 'participantes.latitude' or even without cotes. It passes a string only, to the function.
So, how can I pass the value from this fields beeing selected to the function?
Tryed to use RAW but not work.
Sorry for the big question. thanks! :-)
use App\Classes\MinhasFuncoes;
$mf = new MinhasFuncoes();
$necps = DB::table('necessidades_part')->where('necessidades_part.id_part',"<>",$id_part)
->where(function($query) use ($searchValues){
foreach ($searchValues as $value) {
if(strlen($value)>3){
$query->orwhere('obs','like','%'.($value).'%')
->orwhere('necessidades.descricao','like','%'.($value).'%')
->orwhere('categorias.descricao','like','%'.($value).'%');
}
}
})
->join('participantes','necessidades_part.id_part','=','participantes.id')
->join('necessidades','necessidades_part.id_nec','=','necessidades.id')
->join('categorias','necessidades.id_cat','=','categorias.id')
->join('unidades','necessidades.id_unid','=','unidades.id')
->select('participantes.id as id_part','participantes.nome_part','participantes.latitude',
'participantes.longitude','participantes.nome_part','necessidades_part.id as id_nec_part',
'necessidades_part.id_nec','necessidades_part.quant','necessidades_part.data',
'necessidades_part.obs','necessidades.descricao as desc_nec',
'categorias.descricao as desc_cat','unidades.descricao as desc_unid',
$mf->calcula_distancia($ofps[0]->latitude,$ofps[0]->longitude,'participantes.latitude',
'participantes.longitude').' as distancia')
->orderBy('data','desc')
->paginate(10);
you can not execute your PHP function inside of your DB query. you should use MySQL function instead of that or you should fetch results from the database then map your result just in PHP
I have an existing laravel model, with many where conditions chained to it.
i.e WHERE username='john' AND (updated_at > "2017-01-01" OR ... ) AND ...
I don't know how many previous queries there are, and i don't have access to them. I only have access to the model instance after it has received some where conditions.
i.e i have a function that receives a model as its parameter, and i want
to add an OR condition to already existing wheres
function notDeleted($model) {
// model has already a bunch of where/or where conditions at this point
// i want return rows, that match either all the previous conditions
// OR this new condition that i add inside this function.
}
I would like to add an OR condition, in the following way.
Select * from users WHERE ( (query1 AND query2 AND ...) OR deleted_at IS NULL);
if u simply use
->orWhere, then the query will be
select * from users where query1 AND query2 AND ... OR deleted_at is null
Note: the table names, columns etc are made up for SO post, my actual use case is a bit more complicated.
I had a similar problem and this is how I solved it:
// Create new \Illuminate\Database\Query\Builder with current wheres in a group
$new_query = $query_builder->getQuery()->forNestedWhere();
$new_query->addNestedWhereQuery($query_builder->getQuery());
// Add the new query in another group
$new_query->whereIn($fk_field,
function($q) use ($index_name, $args) {
// Ignore the Sphinx stuff, just add your new condition here.
$q->select(\DB::raw(SphinxSearch::getRawSelect($index_name)))
->where('query', SphinxSearch::getRawQueryString($args));
});
// Replace original \Illuminate\Database\Eloquent\Builder's internal
// \Illuminate\Database\Query\Builder with the new one
$query_builder->setQuery($new_query);
Put the criteria you want to wrap in a closure:
$model->where(function($query) {
$query->where('field', 'value')
->where('field2', 'value');
})
->orWhereNull('deleted_at');
Try to wrap where condition like this below
SomeModel::where(function($q){
$q->where(query1 AND query2 AND ...)
->orWhere(deleted_at IS NULL);
})->get();
Above code is just a sample. You need to modify to your requirements.
For more information check this link Nested Parameter Grouping
I am trying to get the value of a single column using Eloquent:
MyModel::where('field', 'foo')->get(['id']); // returns [{"id":1}]
MyModel::where('field', 'foo')->select('id')->first() // returns {"id":1}
However, I am getting anything but the value 1. How can get that 1?
NOTE: It is possible that the record with field of foo does not exist in the table!
EDIT
I am ideally looking for a single statement that either returns the value (e.g. 1) or fails with a '' or null or other. To give you some more context, this is actually used in Validator::make in one of the rules:
'input' => 'exists:table,some_field,id,' . my_query_above...
EDIT 2
Using Adiasz's answer, I found that MyModel::where('field', 'foo')->value('id') does exactly what I need: returns an integer value or an empty string (when failed).
Laravel is intuitive framework... if you want value just call value() method.
MyModel::find(PK)->value('id');
MyModel::where('field', 'foo')->first()->value('id');
You're using the Eloquent query builder, so by default, it'll return an Eloquent model with only the value you wish.
The method you're looking for is pluck() which exists in the normal query builder (of which the Eloquent one extends) so your code should look as follows:
MyModel::where('field', 'foo')->pluck('id'); // returns [1]
The value() method that is being used in the other answers is an Eloquent model method. Using that means that the framework queries the database, hydrates the model and then returns only that value. You can save yourself a few keystrokes and few CPU cycles by using pluck() and have it handled simply in one query.
I am new to laravel and confused about some query methods.
find($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