Laravel 4 Eloquent Query Builder - Complicated joins with variable -

i'm trying replicate join using laravel query builder:

left join content_userdata on content_id = content.id , user_id = $user_id 

i have discovered can additional "ons" using following function in model extends eloquent

public function scopejoinuserdata($query, $user_id) {     return $query->leftjoin('content_userdata', function($join)     {         $join->on('content_userdata_content_id', '=', 'content.content_id')->on('content_userdata_user_id', '=', 10);     }); } 

but creates 2 problems. firstly cannot $user_id variable function , secondly if hardcode testing purposes have done above (to int "10") laravel encases in ` meaning interpreted column name when shouldn't be, so:

left join `content_userdata` on `content_id` = `content`.`id` , `user_id` = `10` 

so have 2 problems.

1. i cannot $user_id join function when using query scopes
2. even if cannot send variable join since interprets column name

why want this? realise 1 response may place in where. trying way join may not return results (hence left join), since content_userdata table contains things users rating piece of content. if use results nothing in content_userdata table not returned, if can put in join returned due left join.

is there anyway achieve in laravel , if not alternatives, changing ditching laravel on top alternative can think of userdata in separate query.

you need pass variable closure using use keyword - imports variable scope. example:

public function scopejoinuserdata($query, $user_id) {     return $query->leftjoin('content_userdata', function($join) use ($user_id)     {         $join->on('content_userdata_content_id', '=', 'content.content_id')              ->on('content_userdata_user_id',    '=', db::raw($user_id));     }); } 

this php syntax related issue , not laravel limitation!