Laravel如何从每组中获取前3条记录的AVG值

Question

I have a database table, which includes points against the player. A Single player have multiple records in the table. I need to group the records by the player_id. And I am trying to get the average of first 3 records of the each group. I tried to reach this over the last evening. But I had not any luck to solve this.

This is my initial code, And I need to modify this to get the AVG of first 3 records of each group(grouped by player_id)

$oSelect = DB::table('statistics')
          ->where('statistics.league_id', $league_id)
          ->select('id, AVG('statistics.points as points'),player_id, scheduled')
          ->orderBy('statistics.scheduled','DESC')
          ->groupBy('statistics.player_id');

Thank you in advanced

Answer 1

Try this:

$oSelect = DB::table('statistics')
      ->select(DB::raw('id, AVG(statistics.points) as points,player_id,scheduled'))
      ->where('statistics.league_id', $league_id)
      ->orderBy('statistics.scheduled','DESC')
      ->groupBy('statistics.player_id')->limit(3)->get();

Notice: if you get nonaggregated column error that case you must add id column to grouped by columns list or disable the only_full_group_by option in mySql

Disable ONLY_FULL_GROUP_BY