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Question

我有以下两个问题：

$s_name = $this->input->post('check_sur_name');
        $sql = "SELECT * FROM patient WHERE MATCH(s_name) AGAINST ('$s_name' IN BOOLEAN MODE ) or MATCH(f_name) AGAINST (''  IN BOOLEAN MODE)";
        $query = $this->db->query($sql);
        $query = $query->result_array();

        echo json_encode($query);

这是第二个：

$sql = "SELECT * FROM patient WHERE MATCH(s_name) AGAINST ('Mugabe' IN BOOLEAN MODE ) or MATCH(f_name) AGAINST (''  IN BOOLEAN MODE)";
$query = $this->db->query($sql);
$query = $query->result_array();

echo json_encode($query);

第二个脚本运行得很好，并给我一个反馈，但第一个脚本一直在失败，请告诉我在第一个脚本中做错了什么？