如何将常规查询更改为laravel查询（laravel 5）？

我的常规查询如下：

SELECT a.nationality_id, a.nationality_name, b.province_name, c.city_name
FROM tb_general_nationality a
JOIN tb_search_province b ON a.nationality_id = b.country_id
JOIN tb_search_city c ON b.province_id = c.province_id
WHERE b.country_id = 50

我将查询更改为laravel查询，如下所示：

SELECT a.nationality_id, a.nationality_name, b.province_name, c.city_name
FROM tb_general_nationality a
JOIN tb_search_province b ON a.nationality_id = b.country_id
JOIN tb_search_city c ON b.province_id = c.province_id
WHERE b.country_id = 50

服务：

public function listCity($param=null) 
    {
        $city = City::with('province','country')->where('tb_search_province.country_id',$param)->get();        
        echo json_encode($city);        
    }

型号：

城市模式：

namespace App\Models\City;

use Illuminate\Database\Eloquent\Model;

class City extends Model {

    protected $connection = 'pgsql';        

    protected $table = 'tb_search_city';

    public function province()
    {
        return $this->belongsTo('App\Models\Province\Province','province_id','province_id');
    }                  

}

国家模式：

namespace App\Models\Country;

use Illuminate\Database\Eloquent\Model;

class Country extends Model {

    protected $connection = 'pgsql';        

    protected $table = 'tb_general_nationality';

}

省模式：

namespace App\Models\Province;

use Illuminate\Database\Eloquent\Model;

class Province extends Model {

        protected $connection = 'pgsql';        

        protected $table = 'tb_search_province';

        public function country()
        {
            return $this->belongsTo('App\Models\Country\Country','nationality_id','country_id');
        }      

    }

但是，我的laravel查询不起作用。 存在错误。错误如下所示：

SQLSTATE[42P01]: Undefined table: 7 ERROR: missing FROM-clause entry for table "tb_search_province"
LINE 1: select * from "tb_search_city" where "tb_search_province"."c...
^ (SQL: select * from "tb_search_city" where "tb_search_province"."country_id" = 50)

我的桌子是这样的：

tb_search_city (city_id, province_id, city_name)
tb_search_province (province_id, country_id, province_name)
tb_general_nationality (nationality_id, nationality_name)

如何将常规查询更改为laravel查询

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非常感谢

我不确定这是否会导致问题，但我相信您应该是

$this->belongsTo（'App\Models\Country'，等等。

只有一个

国家

。此外，可能会有所帮助。在with函数中，您必须键入province.Country，因为这是一种嵌套关系。