mysql - Codeigniter 查询生成器类

Question

我是使用 codeigniter 查询生成器类的初学者。我在使用查询生成器类转换此查询时遇到了问题。

SELECT tb_country.`countryName`, COUNT(tb_country.countryId) AS totalCustomer FROM tb_customer 
    JOIN tb_city ON tb_city.`cityId` = tb_customer.`cityId`
    JOIN tb_state ON tb_state.`stateId` = tb_city.`stateId`
    JOIN tb_country ON tb_country.`countryId` = tb_state.`countryId`
GROUP BY tb_country.`countryName`

任何答案都会对我有帮助，提前谢谢!

Answer 1

$this->db
     ->select("tb_country.countryName, COUNT(tb_country.countryId) AS totalCustomer", false)
     ->from('tb_customer')
     ->join('tb_city', 'tb_city.cityId = tb_customer.cityId')
     ->join('tb_state', 'tb_state.stateId = tb_city.stateId')
     ->join('tb_country', 'tb_country.countryId = tb_state.countryId')
     ->group_by('tb_country.countryName')
     ->get()
     ->result();