如何在Laravel查询中使用自定义groupBy和LeftJoin？

Question

我尝试了这个查询：

 $this->data = \DB::table('months')->select(DB::raw("months.id, COUNT(clients.id) as total"))
            ->leftJoin('clients','months.id','=','MONTH(created_at)')
            ->groupBy('months.id')
            ->first();

它给我一个错误：

Column not found: 1054 Unknown column 'MONTH(created_at)' in 'on clause' 

如何解决？

Answer 1

尝试指定created_at列的表格。

$this->data = \DB::table('months')->select(DB::raw("months.id, COUNT(clients.id) as total"))
            ->leftJoin('clients','months.id','=','MONTH(clients.created_at)')
            ->groupBy('months.id')
            ->first();