laravel利用subquery使左连接查询右表数据唯一查询 如:表a,连接表b,b中有多条符合查询的记录 1、建立需要的子查询 $sub = DB::table('b')->select(['aid'])->selectRaw('max(id) as id')->grouBy('id'); 2、建立连接查询 $_list = DB::table('a')->leftJoin(DB::raw
2、建立连接查询$_list = DB::table('a')->leftJoin(DB::raw('({$sub->toSql()}) as b),'a.id','=','b.aid)->get()这样就可以使得左连接查询中右表记录只查询一条,避免左表记录重复出现。这里在只是筛选右表中第一条,其它条件暂时还没有实现。
左联接(LEFT JOIN):返回左表中的所有记录,以及右表中匹配的记录。如果右表中没有匹配的记录,则返回NULL。 右联接(RIGHT JOIN):返回右表中的所有记录,以及左表中匹配的记录。如果左表中没有匹配的记录,则返回NULL。 全外联接(FULL OUTER JOIN):返回两个表中的所有记录,如果某个表中...
I'm trying to add a left join to this query I've been using to get nPerGroup of related records. I've created the query in SQL just don't know how to convert it to Laravel query builder code. The reason I want to add a left join is for performance pu
$subQuery = Order::select(DB::raw('orders.user_id, COUNT(*) AS cnt')) ->leftJoin('users', 'orders.user_id', '=', 'users.id') ->where('users.created_at', '>=', $created_at_s) ->where('users.created_at', '<=', $created_at_e) ->groupBy('orders.user_id') ->having...
DB::table('users') ->join('contacts', function (JoinClause $join) { $join->on('users.id', '=', 'contacts.user_id') ->where('contacts.user_id', '>', 5); }) ->get();Subquery JoinsYou may use the joinSub, leftJoinSub, and rightJoinSub methods to join a query to a ...
Subquery JoinsYou may use the joinSub, leftJoinSub, and rightJoinSub methods to join a query to a subquery. Each of these methods receives three arguments: the subquery, its table alias, and a closure that defines the related columns. In this example, we will retrieve a collection of ...
1DB::table('users') 2 ->join('contacts', function (JoinClause $join) { 3 $join->on('users.id', '=', 'contacts.user_id') 4 ->where('contacts.user_id', '>', 5); 5 }) 6 ->get();Subquery JoinsYou may use the joinSub, leftJoinSub, and rightJoinSub methods to join a ...
1DB::table('users') 2 ->join('contacts', function (JoinClause $join) { 3 $join->on('users.id', '=', 'contacts.user_id') 4 ->where('contacts.user_id', '>', 5); 5 }) 6 ->get();Subquery JoinsYou may use the joinSub, leftJoinSub, and rightJoinSub methods to join a ...
Subquery JoinsYou may use the joinSub, leftJoinSub, and rightJoinSub methods to join a query to a subquery. Each of these methods receive three arguments: the subquery, its table alias, and a Closure that defines the related columns:$latestPosts = DB::table('posts') ->select('user...