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mysql释放结果内存代码示例

Jun 07, 2016 pm 04:20 PM
mysqlcodeMemoryExampleresultfreed

mysql释放结果内存代码示例(相关mysql视频教程推荐:《mysql教程》)

定义和用法

mysql_free_result() 函数释放结果内存。

如果成功,则返回 true,如果失败,,则返回 false。

语法

mysql_free_result(data)参数 描述

data 必需。要释放的结果标识符。该结果标识符是从 mysql_query() 返回的结果。

提示和注释

注释:mysql_free_result() 仅需要在考虑到返回很大的结果集时会占用多少内存时调用。在脚本结束后所有关联的内存都会被自动释放。

例子

$con = mysql_connect("localhost", "peter", "abc123");
  if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }
  $db_selected = mysql_select_db("test_db",$con);
  $sql = "SELECT * from Person";
  $result = mysql_query($sql,$con);
  print_r(mysql_fetch_row($result));
  // 释放内存
  mysql_free_result($result);
  $sql = "SELECT * from Customers";
  $result = mysql_query($sql,$con);
  print_r(mysql_fetch_row($result));
  mysql_close($con);
  ?>

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