Laravel SQL how to add table fields value [duplicate]

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• Laravel 4 eloquent WHERE with OR AND OR? 7 answers

I'm trying to get the sum of two team score but it returns null.

DB::table('team_competition_statistics')
->select([
    DB::raw('SUM(sGames) AS GP'),
    DB::raw('SUM(sPointsAverage) as AVGP'),
    DB::raw('SUM(sAssistsAverage) as AVGA'),
    DB::raw('SUM(sReboundsTotalAverage) as AVGR'),
    DB::raw('SUM(sStealsAverage) as AVGS'),
    DB::raw('SUM(sBlocksAverage) as AVGB')
])
->where('competitionId', $competitionId)
->where('periodNumber', 0)
->where('teamId', $id1)
->where('teamId', $id2)
->get();

via Chebli Mohamed