I want to get data from database with range like 0 to 50 and 51 to 100, this is possible? if possible please talk me how to do that.
$users = User::all();
I am not able to get clearly what do you want. But I have provided some examples below that might work for you.
$users = DB::table('users')
->whereBetween('id', [1, 50])
->get();
Also try skip and take.
You may use the skip and take methods to limit the number of results returned from the query or to skip a given number of results in the query:
$users = DB::table('users')->skip(50)->take(50)->get();
Alternatively, you may use the limit and offset methods. These methods are functionally equivalent to the take and skip methods, respectively:
$users = DB::table('users')
->offset(50)
->limit(50)
->get();
Hope this helps!
There are a number of options available to you. If you're looking to obtain a working data set of x results at a time and not concerned about the id of the results, then one of the following might be of use:
Pagination
Chunking results
Both of the above will allow you to define the size/number of records returned for your data set.
If you're looking to return records between specific id values, then you'll want to use something like whereBetween on your database queries. The whereBetween clause can be used in conjunction with the pagination and chunking.
Related
I know you can do a withSum on a relationship like this:
$posts = Post::withSum('comments', 'votes')->get();
But I like to chain an additional where clause on this, something like this (doesn't work but as an example):
$posts = Post::withSum('comments', 'votes', function (Builder $query) {
$query->where('comments.votes', '>', 5);
})->get()
Is that possible?
While Aggregating Related Models is not explicit about this in the documentation, it does give us a clue by mentioning:
If you need to set additional query constraints on the count query, you may pass an array keyed by the relationships you wish to count. The array values should be closures which receive the query builder instance.
If you need to set additional query constraints on the count query, you can pass an encoded array by the relationships you want to count. The values in the array must be anonymous functions that receive the query builder instance.
So, we can take advantage of that anonymous function to modify the query builder instance so that instead of taking the default values (which would use the aggregate 'count'), and pass it the subquery we want to do, which is the where clause and the 'sum' of the column.
Said that, your query cuold looks like:
Post::withCount(['comments as comments_sum_votes' => function($query) {
$query->where('comments.votes', '>', 5)->select(DB::raw('sum(votes)'));
}])->get()
I'm a bit new to this, and was originally trying to check if my model was returning results with isEmpty(), but thought I'd try count() instead, then I came across the following:
I've got the following code, which returns data from my model:
$results = Game::where('code', '=', $code)->with('genre', 'creator')
And whether I use first() or get() combined with count(result) or $results->count() I get different values, and I'm not sure why.
when using ->first()
dd($results->count()) = 11930 // Number of rows in the db
when using ->get()
dd($results->count()) = 1 // What I'd expect the query to return
when using ->first()
dd(count($results)) = "count(): Parameter must be an array or an object that implements Countable"
when using ->get()
dd(count($results)) = 1
I don't understand 1) why when using first, the count is the same as every row in the db. 2) Why count() can't be used with first().
Is anyone able to shed some light as to why I can't use count on first as I'd like to?
Update:
I'm also not able to use ->isEmpty() with ->first() but can with ->get()...?
When I try using it with first, I get Illuminate\Database\Query\Builder::isEmpty does not exist.
Disclaimer: I'm not sure why your database count and your results count aren't the same, however I can shed some light on the different types of count.
Game::where('code', '=', $code)->count();
This is being called on a query builder instance. It is run on the database query, without selecting all the rows. Check out the title Aggregates here: https://laravel.com/docs/5.7/queries
Game::where('code', '=', $code)->get()->count();
As soon as your use get() laravel selects the rows, boots them all as models, and creates a collection. This count is on the collection (a bit like an array) so just gets the number that are returned (i.e. if they are paginated or anything like that it will just get that amount). Check out Count here.
Game::where('code', '=', $code)->first()->count();
This is being run on the first returned model... unless you've written it, a default laravel model won't have a count() method.
count($results)
Finally, count() when not a class method is just the default php function that returns the length of an array or other object (documentation).
First of all,
get() returns collection of objects while first() returns modal object of query.
$results = Game::where('code', '=', $code)->with('genre', 'creator')
dd($results->count()) = 11930 // Number of rows in the db
when using ->get()
$results = Game::where('code', '=', $code)->with('genre', 'creator')->get()
dd($results->count()) = 1
because it has collection, which contains numbers of objects of database data. As ->count getting only one collection so it returns 1.
I have a many to many relationship that looks like so
batches -> batch_contributors -> contributors
I am running into an issue when attempting to paginate, I am doing the following:
$contributions = Batch::with('contributors')->where('id', '=' , $batchid)->paginate(10);
Here are samples from my parsed JSON (faker data)
parsed JSON
end of parsed JSON
My problem is the contributor records are listed under the single batch record, so pagination is seeing this and loading all 100 contributors on the first page instead of 10 per page.
How do I get pagination to look at the contributor level instead of the batch level?
You can just invert the call and get contributors where batchId is equal to the one u parse, something like this:
Contributor::with(['batches' => function($query) use ($batchId) {
$query->where('id', $batchId);
}])->paginate(10);
Try this:
Batch::with('contributors', function($query){
$query->take(10); // to take 10 contributors for all the 10 selected Batchs
})->where('id', '=' , $batchid)->paginate(10);
Laravel will get 10 contributors in this case, and try to map them into the batchs, So If those 10 contributors belong to one batch, the rest batchs won't have any contributors.
Hi how can I select limited number of all the item from model and the selection with certain names.
eg:
$product = Product::all()->limit(4)->select('id','name');
Most of example start with Product::find(1) but my case, I don't have id. Thanks
Use the other methods first, then call get at the end:
$products = Product::limit(4)->select('id', 'name')->get();
Limit Query Results
To limit the number of results returned from the query, or to skip a given number of results in the query, you may use the skip() and take() methods:
Example of User model which extends Eloquent:
$users = User::take(5)->skip(10)->get();
Product::all() will be used when get all data without any condition. You need to use get method.
you need to
$products = Product::select('id', 'name')->limit(4)->get();
So I'm trying to get the number of distinct pids on a query, but the returned value is wrong.
This is what I try to do:
$ad->getcodes()->groupby('pid')->distinct()->count()
what returns the value "2", while the value it should return, should be "1".
As a workaround, I'm doing this:
count($ad->getcodes()->groupby('pid')->distinct()->get())
what works fine and returns "1"
Is there any rule where count and distinct cannot be on the same query? I find the workaround kind of "heavy", I would like to make the original query work :(
The following should work
$ad->getcodes()->distinct()->count('pid');
A more generic answer that would have saved me time, and hopefully others:
Does not work (returns count of all rows):
DB::table('users')
->select('first_name')
->distinct()
->count();
The fix:
DB::table('users')
->distinct()
->count('first_name');
Anyone else come across this post, and not finding the other suggestions to work?
Depending on the specific query, a different approach may be needed. In my case, I needed either count the results of a GROUP BY, e.g.
SELECT COUNT(*) FROM (SELECT * FROM a GROUP BY b)
or use COUNT(DISTINCT b):
SELECT COUNT(DISTINCT b) FROM a
After some puzzling around, I realised there was no built-in Laravel function for either of these. So the simplest solution was to use use DB::raw with the count method.
$count = $builder->count(DB::raw('DISTINCT b'));
Remember, don't use groupBy before calling count. You can apply groupBy later, if you need it for getting rows.
You can use the following way to get the unique data as per your need as follows,
$data = $ad->getcodes()->get()->unique('email');
$count = $data->count();
Hope this will work.
I had a similar problem, and found a way to work around it.
The problem is the way Laravel's query builder handles aggregates. It takes the first result returned and then returns the 'aggregate' value. This is usually fine, but when you combine count with groupBy you're returning a count per grouped item. So the first row's aggregate is just a count of the first group (so something low like 1 or 2 is likely).
So Laravel's count is out, but I combined the Laravel query builder with some raw SQL to get an accurate count of my grouped results.
For your example, I expect the following should work (and let you avoid the get):
$query = $ad->getcodes()->groupby('pid')->distinct();
$count = count(\DB::select($query->toSql(), $query->getBindings()));
If you want to make sure you're not wasting time selecting all the columns, you can avoid that when building your query:
$query = $ad->select(DB::raw(1))->getcodes()->groupby('pid')->distinct();
I came across the same problem.
If you install laravel debug bar you can see the queries and often see the problem
$ad->getcodes()->groupby('pid')->distinct()->count()
change to
$ad->getcodes()->distinct()->select('pid')->count()
You need to set the values to return as distinct. If you don't set the select fields it will return all the columns in the database and all will be unique. So set the query to distinct and only select the columns that make up your 'distinct' value you might want to add more. ->select('pid','date') to get all the unique values for a user in a day
Based on Laravel docs for raw queries I was able to get count for a select field to work with this code in the product model.
public function scopeShowProductCount($query)
{
$query->select(DB::raw('DISTINCT pid, COUNT(*) AS count_pid'))
->groupBy('pid')
->orderBy('count_pid', 'desc');
}
This facade worked to get the same result in the controller:
$products = DB::table('products')->select(DB::raw('DISTINCT pid, COUNT(*) AS count_pid'))->groupBy('pid')->orderBy('count_pid', 'desc')->get();
The resulting dump for both queries was as follows:
#attributes: array:2 [
"pid" => "1271"
"count_pid" => 19
],
#attributes: array:2 [
"pid" => "1273"
"count_pid" => 12
],
#attributes: array:2 [
"pid" => "1275"
"count_pid" => 7
]
$solution = $query->distinct()
->groupBy
(
[
'array',
'of',
'columns',
]
)
->addSelect(
[
'columns',
'from',
'the',
'groupby',
]
)
->get();
Remember the group by is optional,this should work in most cases when you want a count group by to exclude duplicated select values, the addSelect is a querybuilder instance method.
Wouldn't this work?
$ad->getcodes()->distinct()->get(['pid'])->count();
See here for discussion..
Distinct do not take arguments as it adds DISTINCT in your sql query, however, you MAY need to define the column name that you'd want to select distinct with. Thus, if you have
Flight->select('project_id')->distinct()->get() is equialent to SELECT DISTINCT 'project_id' FROM flights and you may now add other modifiers like count() or even raw eloquent queries.
Use something like this
DB::table('user_products')->select('user_id')->distinct()->pluck('user_id')->toArray();
This was working for me so
Try This:
$ad->getcodes()->distinct('pid')->count()
try this
$ad->getcodes()->groupby('pid')->distinct()->count('pid')