groupBy in laravel function similarly to distinct?

Question

My records in 'answers table':

**id    question_id   answer**

  20      12          app/Http/routes.ph
  21      13          uri
  22      13          closure
  23      14          controller
  24      15          class name
  25      15          App\Http\Controllers
  26      16          for displayh

My code to retrieve data:

$qas= DB::table('answers')
         ->groupBy('question_id')
         ->get();
        dump($qas);
    }

I get only 5 records instead of 7; where the other 2 records? It works similarly to distinct function which is not my intention.

How to write code to get all 7 record which are grouped by 'question_id'?

if my answer was helpful, please choose my answer as best answer and upvote it. — Alexey Mezenin, Mar 15 '16 at 14:19

score 0 · Answer 1 · answered Feb 19 '16 at 04:00

0

Understand the concept of GroupBy, its mean that, it will consider same items as one, eg 14, 14-> 14 | 13,13-> 13 if you want to get all answer, then you have to write this

DB::table('answers')->get();

Edited

distinct and group by will do same action in your case. If You can explain your problem in more details, then may be there is possible solution are.

answered Feb 19 '16 at 04:00

Qazi

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My table "answer table' has field: id, question_id, and answer. I want to get all records for answer column, but the records must be categoried or group by question column. – Misterk Feb 19 '16 at 04:50
`DB::table('answers')->select('question_id', DB::raw(group_concat(answer SEPARATOR ',') AS ans) )->groupBy('question_id')->get();` for reference have a look [Link 1](http://stackoverflow.com/questions/149772/how-to-use-group-by-to-concatenate-strings-in-mysql?answertab=votes#tab-top) [Link 2](http://stackoverflow.com/questions/15273118/how-to-use-group-by-to-concat-strings-in-mysql?answertab=votes#tab-top) [Link 3](http://www.giombetti.com/2013/06/06/mysql-group_concat/) – Qazi Feb 19 '16 at 05:16

score 0 · Answer 2 · answered Feb 19 '16 at 05:14

0

You're talking about result with 7 rows, but that's not grouping. Maybe you're talking about ordering instead of grouping? If so, you'd want to use ->orderBy('question_id', 'asc'), that will give you 7 rows, sorted by question_id.

answered Feb 19 '16 at 05:14

Alexey Mezenin

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score 0 · Answer 3 · answered Feb 19 '16 at 16:43

In SQL, GROUP BY clause is useful when you need to aggregate the result in a sort of way for example for SUM or AVERAGE of data.

Your case is different, you don't need to aggregate data using some function, you simply need a different data structure other than a simply and flat result list.

For your need, you should avoid GROUP BY, and reorder data in your code in a programmatic way.

groupBy in laravel function similarly to distinct?

3 Answers3