我有一个查询。
我在mysql数据库中有3个表。
我想用这些规则连接我的表,多个表的多个列连接到同一表的一列。
MySQL示例如下。预先感谢。
SELECT
s.*,e.*
, m1.m_id AS 'mid'
, m1.m_name AS 'mname'
, m2.m_id AS 'bid'
, m2.m_name AS 'bname'
, e1.e_id AS 'tid'
, e1.e_name AS 'tname'
, e2.e_id AS 'topid'
, e2.e_name AS 'topname'
FROM s s,e e
INNER JOIN m m1
ON s.s_m_id = m1.m_id
INNER JOIN m m2
ON s.s_b_id = m2.m_id
INNER JOIN e e1
ON s.s_t_id = e1.e_id
INNER JOIN e e2
ON s.s_t_t_id = e2.e_id
WHERE s_id =1
答案 0 :(得分:0)
$this->db->select("s.*,e.*
, m1.m_id AS 'mid'
, m1.m_name AS 'mname'
, m2.m_id AS 'bid'
, m2.m_name AS 'bname'
, e1.e_id AS 'tid'
, e1.e_name AS 'tname'
, e2.e_id AS 'topid'
, e2.e_name AS 'topname'");
$this->db->from("FROM s");
$this->db->join("m m1
s.s_m_id = m1.m_id","inner");
$this->db->join("m m2
s.s_b_id = m2.m_id","inner");
$this->db->join("e e1
s.s_t_id = e1.e_id","inner");
$this->db->join(" e e2
s.s_t_t_id = e2.e_id","inner");
$this->db->where('s_id','1');
$this->db->get();
答案 1 :(得分:0)
您的代码不起作用吗?尝试删除
上的“ FROM”self.progressView.setProgress(0, animated: false)
self.progressLabel.text = "0.0 %"
self.finalUrlLabel.text = ""
let request = URLRequest.init(url: URL.init(string: "http://techslides.com/demos/samples/sample.mp4")!)
let downloadKey = SDDownloadManager.shared.dowloadFile(withRequest: request,
inDirectory: directoryName,
withName: nil,
onProgress: { [weak self] (progress) in
let percentage = String(format: "%.1f %", (progress * 100))
self?.progressView.setProgress(Float(progress), animated: true)
self?.progressLabel.text = "\(percentage) %"
print("percentage",percentage)
}) { [weak self] (error, url) in
if let error = error {
print("Error is \(error as NSError)")
} else {
if let url = url {
print("Downloaded file's url is \(url.path)")
self?.finalUrlLabel.text = url.path
}
}
}
print("The key is \(downloadKey!)")
let dasd = SDDownloadManager.shared.ongoingDownloads
print("dasd",dasd.count)