如何将sql联合转换为codeigniter方式

Question

如何使用PHP CodeIgniter框架进行UNION查询，当我执行此查询时出现错误

Every derived table must have its own alias

型号

function search_blog($title){
$query = $this->db->query("SELECT * FROM (
                SELECT id,section,title,img,year,lastupdateon AS ondate,'moves' AS dept,STATUS FROM movies
                UNION
                SELECT ID,section,Title,img,year,lastupdateon AS ondate,'kid' AS dept,STATUS FROM kids
                UNION
                SELECT ID,views,Title,img,version AS year,ondate,'software' AS dept,STATUS FROM soft
                UNION
                SELECT ID,section,Title,img,'PC Game' AS year,ondate,'game' AS dept,STATUS FROM games
                UNION
                SELECT ID,season,Title,img,type AS year,lastupdatedon AS ondate,'tvshow' AS dept,STATUS FROM tvshows
                )");
        $this->db->like('Title', $title , 'after');
        $this->db->order_by('ondate', 'DESC');
        $this->db->limit(10);
        return $this->db->get($query)->result();
    }

如何更改

Answer 1

您可以简单地通过为每个表添加查询并像这样使用并集将它们加入来进行此操作

$this->db->select('ID,section,title,img,year,lastupdateon AS ondate,`moves` AS dept,STATUS');
$this->db->from('movies');
$query1 = $this->db->get_compiled_select();

$this->db->select('ID,section,title,img,year,lastupdateon AS ondate,`kid` AS dept,STATUS');
$this->db->from('kids');
$query2 = $this->db->get_compiled_select();

$this->db->select('ID,views,title,img,version AS year,ondate,`software` AS dept,STATUS');
$this->db->from('soft');
$query3 = $this->db->get_compiled_select();


$this->db->select('ID,section,title,img,'PC Game' AS year,ondate,`game` AS dept,STATUS');
$this->db->from('games');
$query4 = $this->db->get_compiled_select();

$this->db->select('ID,season,title,img,type AS year,lastupdatedon AS ondate,`tvshow` AS dept,STATUS');
$this->db->from('tvshows');
$query5 = $this->db->get_compiled_select();

$this->db->like('title', $title , 'after');
$this->db->order_by('ondate', 'DESC');
$this->db->limit(10);


$query = $this->db->query($query1 . ' UNION ' . $query2. ' UNION ' . $query3. ' UNION ' . $query4. ' UNION ' . $query5);

return $this->db->get($query)->result();