Laravel4クエリビルダー-groupByMaxDate

これは、laravelでgroupByMaxDateを取得するための最も簡単で最短の方法です。 user_idでグループ化された最大日付の行を取得します 。

       $rows = DB::table('papers')
               ->select(DB::raw('id, max(paper_update) as year,user_id'))
               ->groupBy('user_id')
               //->orderBy('paper_update', 'desc')
               ->get();

このlaravelクエリは、次のようなmysqlクエリを作成します

select id, max(paper_update) as year from `papers` group by `user_id`;

出力はになります

Array
(
    [0] => stdClass Object
        (
            [id] => 4
            [year] => 30-5-2013 
            [user_id] => 1
        )

    [1] => stdClass Object
        (
            [id] => 5
            [year] => 30-5-2013
            [user_id] => 2
        )

    [2] => stdClass Object
        (
            [id] => 6
            [year] => 30-5-2014
            [user_id] => 3
        )

    [3] => stdClass Object
        (
            [id] => 7
            [year] => 30-5-2014
            [user_id] => 4
        )
    [4] => stdClass Object
        (
            [id] => 10
            [year] => 30-5-2016
            [user_id] => 5
        )
)