116 lines
2.6 KiB
PHP
116 lines
2.6 KiB
PHP
<?php
|
||
/****************************************************
|
||
* NKeditor PHP
|
||
* 本PHP程序是演示程序，建议不要直接在实际项目中使用。
|
||
* 如果您确定直接使用本程序，使用之前请仔细确认相关安全设置。
|
||
* **************************************************
|
||
* 简易数据库, 单表 100w 条数据，查询一页数据在 0.015 秒左右
|
||
* 缺陷，无法排序，如果要排序的话，那么不适合使用 SimpleDB， 请使用 mysql 或者 mongdb
|
||
* User: yangjian
|
||
* Date: 17-10-14
|
||
* Time: 下午5:15
|
||
*/
|
||
|
||
class SimpleDB {
|
||
|
||
/**
|
||
* 文件资源
|
||
* @var null|resource
|
||
*/
|
||
private $handler = null;
|
||
|
||
/**
|
||
* 初始化，打开文件
|
||
* SimpleDB constructor.
|
||
* @param $dbname
|
||
*/
|
||
public function __construct($dbname)
|
||
{
|
||
$dataDir = __DIR__."/data/";
|
||
if (!file_exists($dataDir)) {
|
||
mkdir($dataDir);
|
||
}
|
||
$this->handler = fopen($dataDir.$dbname.'.db', 'a+');
|
||
}
|
||
|
||
/**
|
||
* 写入一行数据
|
||
* @return bool
|
||
*/
|
||
public function putLine($data) {
|
||
|
||
if ($this->handler != null) {
|
||
fwrite($this->handler, $this->seralize($data));
|
||
}
|
||
return false;
|
||
|
||
}
|
||
|
||
/**
|
||
* 分页获取数据列表
|
||
* @param $key
|
||
* @return array|null
|
||
*/
|
||
public function getDataList($page, $pagesize) {
|
||
|
||
if($page <= 0) {
|
||
$page = 1;
|
||
}
|
||
$offset = ($page - 1) * $pagesize;
|
||
//循环读取数据
|
||
$datas = [];
|
||
$counter = 0;
|
||
while (!feof($this->handler)) {
|
||
if ($counter < $offset) {
|
||
fgets($this->handler); //移动指针到下一行
|
||
$counter++;
|
||
continue;
|
||
}
|
||
if (count($datas) == $pagesize) {
|
||
break;
|
||
}
|
||
$line = fgets($this->handler);
|
||
if (!empty($line)) {
|
||
$datas[] = $this->unseralize($line);
|
||
}
|
||
}
|
||
|
||
return $datas;
|
||
}
|
||
|
||
/**
|
||
* 序列化数据
|
||
* @param $data
|
||
* @return string
|
||
*/
|
||
private function seralize($data) {
|
||
|
||
$break = "\n"; //换行符
|
||
if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
|
||
$break = "\r\n";
|
||
}
|
||
return json_encode($data, JSON_UNESCAPED_UNICODE).$break;
|
||
|
||
}
|
||
|
||
/**
|
||
* 反序列化
|
||
* @param $data
|
||
* @return mixed
|
||
*/
|
||
private function unseralize($data) {
|
||
|
||
return json_decode($data, true);
|
||
|
||
}
|
||
|
||
/**
|
||
* 关闭文件
|
||
*/
|
||
public function __destruct()
|
||
{
|
||
if ($this->handler != null) {
|
||
fclose($this->handler);
|
||
}
|
||
}
|
||
} |