1、獲取一個表的全部數據
$this->db->get('mytable');
// Produces: SELECT * FROM mytable
第二和第三個參數允許你設置一個結果集每頁紀錄數(limit)和結果集的偏移(offset)
$query = $this->db->get('mytable', 10, 20);
// Produces: SELECT * FROM mytable LIMIT 20, 10
設置要查詢的字段
$this->db->select('title, content, date');
$query = $this->db->get('mytable');
// Produces: SELECT title, content, date FROM mytable