我有三张table table1: documents (id, code, content) table2: files (id, code, filename) table3: tags (documentId, tag) 在我的页面上，我必须在表视图中显示所有文档。喜欢
code | content 123 | This is a sample document with file**files.filename**and tags**tags.tag** 每个文档可以有许多文件和标记
这是我现在的密码。

return $this->db
    ->select('t1.id, t1.barcode, t1.sub, t1.source_type, t1.sender, t1.address, t1.description, t1.receipient, t1.status, t2.id as fileId, t3.tag as docTag')
    ->select('DATE_FORMAT(t1.datetime_added, \'%m/%d/%Y-%h:%i %p\') as datetime_added', FALSE)
    ->from('documents as t1')
    ->join('files as t2', 't2.barcode = t1.barcode', 'left')
    ->join('tags as t3', 't3.id = t1.id')
    ->order_by('id', 'desc')
    ->get()->result_array();