Codeigniter 2 多重连接和 where 语句答案

【问题标题】：Codeigniter 2 multiple join and where statementCodeigniter 2 多重连接和 where 语句
【发布时间】：2018-05-30 02:23:48
【问题描述】：

更新代码

$office = $this->session->userdata('department');

$query = "SELECT `doc`.`id`, `doc`.`barcode`, `doc`.`sub`, `doc`.`source_type`, `doc`.`sender`, `doc`.`address`, `doc`.`description`, `doc`.`receipient`, `doc`.`status`, DATE_FORMAT(`doc`.`datetime_added`, '%m/%d/%Y-%h:%i %p') as datetime_added,
          (SELECT GROUP_CONCAT(`tag`) FROM `tags` WHERE `tags`.`documentId` = `doc`.`id` GROUP BY `tags`.`documentId`) as `tags`
          FROM `documents` AS `doc`
          JOIN `transactions` AS `trans` ON `doc`.`id` = `trans`.`document_id`
          JOIN `trackers` AS `track` ON `doc`.`id` = `track`.`document_id`
          WHERE `doc`.`status` = 'Processing'
          AND `track`.`action` = '1')
          AND `track`.`location` = '$office'
          ORDER BY `doc`.`id` DESC";
$go = $this->db->query($query)->result_array();
var_dump($go); exit();

我试图完成的是显示位于我们办公室的所有文档，这些文档正在处理并且具有操作1。文件可能有备忘录、请求、财务等标签。输出不正确，未显示我们办公室的所有记录。我认为 WHERE 子句有问题？我的代码中的罪魁祸首可能是什么？

【问题讨论】：

您将需要加入一个子查询，该子查询通过id 在tags 表上执行GROUP_CONCAT，以生成每个文档的所有标签的列表。我在您的代码中看到太多问题，无法尝试正式回答。
嗨@TimBiegeleisen 我目前正在做一个自定义查询。稍后我会更新代码。你看到了什么问题，所以我可以解决它？非常感谢！

标签： php mysql sql join codeigniter-2

【解决方案1】：

通过删除围绕 1 的单引号来更新您的查询：

$query = "SELECT `doc`.`id`, `doc`.`barcode`, `doc`.`sub`, `doc`.`source_type`, `doc`.`sender`, `doc`.`address`, `doc`.`description`, `doc`.`receipient`, `doc`.`status`, DATE_FORMAT(`doc`.`datetime_added`, '%m/%d/%Y-%h:%i %p') as datetime_added,
          (SELECT GROUP_CONCAT(`tag`) FROM `tags` WHERE `tags`.`documentId` = `doc`.`id` GROUP BY `tags`.`documentId`) as `tags`
          FROM `documents` AS `doc`
          JOIN `transactions` AS `trans` ON `doc`.`id` = `trans`.`document_id`
          JOIN `trackers` AS `track` ON `doc`.`id` = `track`.`document_id`
          WHERE `doc`.`status` = 'Processing'
          **AND `track`.`action` = 1)**
          AND `track`.`location` = '$office'
          ORDER BY `doc`.`id` DESC";

【讨论】：

【解决方案2】：

$this->db->select("doc.id, doc.barcode, doc.sub, doc.source_type, doc.sender, doc.address, doc.description, doc.receipient, doc.status, DATE_FORMAT(doc.datetime_added, %m/%d/%Y-%h:%i %p) as datetime_added,
      (SELECT GROUP_CONCAT(tag) FROM tags WHERE tags.documentId = doc.id GROUP BY tags.documentId) as tags")
      ->from("documents AS doc") 
      ->join("transactions AS trans",'doc.id=trans.document_id')
      ->join("trackers AS track",'doc.id=track.document_id')
      ->where("doc.status","Processing")
      ->andWhere("track.action","1")
      ->andWhere("doc.id",$office)
      ->order_by("doc.id", "DESC");

【讨论】：