一个简单php数据库备份程序

<?php
/** 备份数据库 生成.sql文件
     * @param $browseinfo  String  浏览器版本
     * return $browseinfo
     */
    function createsql(){
        //创建个日期
        $timer1 = time();
        $path = "my_sql/";
        $content =gettables();
        $filename = $path.$timer1.".sql";
  
        //先判断文件夹在不在
         if(!file_exists($path)){
        //如果不存在生成这个目录,0777表示最大的读写权限
            if(mkdir($path,0777)){
            //echo"新建立目录"; 
            }
        }

        //判断文件是否存在
        if(!file_exists($filename)){
            //如果文件不存在,则创建文件
            @fopen($filename,"w");

            //判断文件是否可写
            if(is_writable($filename)){
            //打开文件以添加方式即"a"方式打开文件流
                if(!$handle =  fopen($filename,"a")){
                    echo"文件不可打开";
                    exit();
                }

            if(!fwrite($handle,$content)){
                echo"文件不可写";
                exit();
            }

        //关闭文件流
        fclose($handle);
        echo "生成文件并保存首次内容";
       
    }else {
        echo"文件$filename不可写";
    }
        }else{
            if(is_writable($filename)){
            //以添加方式打开文件流
            if(!$handle = fopen($filename,"a")){
                echo"文件不可打开";
                exit();
            }
            fclose($handle);
            }else{
                echo "文件$filename不可写";
            }
    }
}

    /**
     * 获得数据库中的表名
     * return $str 循环生成数据库建表和插入值的sql语句
     */
    function gettables(){
        $mysqli = new mysqli("localhost","root","","bbs");
        $str = '';
        if ($result = $mysqli->query("SHOW TABLES")) {
            while($row = $result->fetch_row()){
                $str.= data2sql($row[0])."<br/>";
            }
            $mysqli->close();
            return $str;
        }  
   
    }
   

    /**
     * 获得数据库中的表结构和值
     * return $tabledump 返回一个表中的结构和值的sql语句
     */
    function data2sql($table){ 
     $mysqli = new mysqli("localhost","root","","bbs");
        /* check connection */
        if (mysqli_connect_errno()) {
            printf("Connect failed: %sn", mysqli_connect_error());
        exit();
    }
         $tabledump = "DROP TABLE IF EXISTS $table;n";
         $result = $mysqli->query("SHOW CREATE TABLE $table");
         $create = $result->fetch_row();
         $tabledump .= $create[1].";nn";
 
         $rows = $mysqli->query("SELECT * FROM $table");
         $numfields = $rows->num_rows;

            while ($row = $rows->fetch_row()){
             $comma = "";
             $tabledump .= "INSERT INTO $table VALUES(";
              for($i = 0; $i < $numfields; $i++)
              {
                 $tabledump .= $comma."'".mysql_escape_strin
g($row[$i])."'";
                 $comma = ",";
              }
             $tabledump .= ");n";
          }
         $tabledump .= "n";
 
          return $tabledump;
      }
?>

public static function stringFromColumnIndex($pColumnIndex = 0)
    {
        //  Using a lookup cache adds a slight memory overhead, but boosts speed
        //  caching using a static within the method is faster than a class static,
        //      though it's additional memory overhead
        static $_indexCache = array();
 
        if (!isset($_indexCache[$pColumnIndex])) {
            // Determine column string
            if ($pColumnIndex < 26) {
                $_indexCache[$pColumnIndex] = chr(65 + $pColumnIndex);
            } elseif ($pColumnIndex < 702) {
                $_indexCache[$pColumnIndex] = chr(64 + ($pColumnIndex / 26)) .
                                              chr(65 + $pColumnIndex % 26);
            } else {
                $_indexCache[$pColumnIndex] = chr(64 + (($pColumnIndex - 26) / 676)) .
                                              chr(65 + ((($pColumnIndex - 26) % 676) / 26)) .
                                              chr(65 + $pColumnIndex % 26);
            }
        }
        return $_indexCache[$pColumnIndex];
    }

PHPExcel_Cell::stringFromColumnIndex($i); // 从o开始

PHPExcel_Cell::columnIndexFromString(‘AA’);

  select * from tablename order by rand() limit 1 

$query= "SELECT count(*) as count FROM recommends";
....
$max_num = $row['count']; // 取记录总数
srand((double)microtime()*1000000); // 随机数种子
$se_pos = rand(0, $max_num); // 随机数范围
$length = 6; // 记录条数
if (($max_num - $se_pos) <= $length) {
    $se_pos = $max_num - $se_pos; // 记录数不足6条的情况
}

$query = "SELECT * FROM recommendsn limit ".$se_pos.",".$length;

<?php

$db = mysql_connect("localhost", "root");

mysql_select_db("xyj",$db);

$result=mysql_query("SELECT * FROM obj",$db);

$max_num=mysql_num_rows($result);//取得数据库的记录数

srand((double)microtime()*10000000); //生成随机数种子。

$se_pos=rand(0, $max_num-1); //从0到最大记录数取随机数

$length=30; //设定共取多少条记录

//下面是取出指定数目的记录。

$result_lim=mysql_query("select * from obj limit $se_pos,$length",$db);

$myrow_lim=mysql_fetch_array($result_lim);

printf("%sn", $se_pos);//显示随机得到的记录号

printf("%sn", $myrow_lim["name"]);//显示随机得到的记录的name字段

require_once("backdata.class.php");
$link = @mysql_connect("localhost","数据库名","密码") or die ('Could not connect to server.');
mysql_query("use cms",$link);
mysql_query("set names utf8",$link);

$dbbck = new backupData($link);//实例化它，只要一个链接标识就行了

//备份数据时，如想备份一个数据库中的所有表，你可这样写：
$dbbck->backupTables("cms","./",array('*'));

//备份数据时，如想备份一个数据库中的仅一个表时，你可这样写：
$dbbck->backupTables("cms","./",array('user'));

//备份数据时，如想备份一个数据库中的多个表时，你可这样写：
$dbbck->backupTables("cms","./",array('user','acl','informatoin'));

//注解：$dbbck->backupTables("参1","参2",array());中，

<?php
/*
*
*一个简单的Mysql备份数据类
*
*/
class backupData{
    private    $mysql_link;//链接标识
    private    $dbName;    //数据库名
    private    $dataDir;     //数据所要存放的目录
    private    $tableNames;//表名

    public function __construct($mysql_link){
         $this->mysql_link = $mysql_link;
    }
    public function backupTables($dbName,$dataDir,$tableNames){//开始备份
        $this->dbName  = $dbName;
        $this->dataDir  = $dataDir;
        $this->tableNames = $tableNames;
        $tables=$this->delarray($this->tableNames);
        $sqls='';
        foreach($tables as $tablename){
            if($tablename==''){//表不存在时
                continue;
            }
           
            //************************以下是形成SQL的前半部分**************
            //如果存在表，就先删除
            $sqls .= "DROP TABLE IF EXISTS $tablename;n";
            //读取表结构
            $rs = mysql_query("SHOW CREATE TABLE $tablename",$this->mysql_link); 
            $row=mysql_fetch_row($rs);
            //获得表结构组成SQL
            $sqls.=$row['1'].";nn";
            unset($rs);
            unset($row);
           
            //************************以下是形成SQL的后半部分**************
            //查寻出表中的所有数据
            $rs=mysql_query("select * from $tablename",$this->mysql_link);
            //表的字段个数
            $field=mysql_num_fields($rs);
            //形成此种SQL语句:"INSERT INTO `groups` VALUES('1499e0ca25988d','主任','','0');"
            while($rows=mysql_fetch_row($rs)){
                $comma='';//逗号
                $sqls.="INSERT INTO `$tablename` VALUES(";
                for($i=0;$i<$field;$i++){
                    $sqls.=$comma."'".$rows[$i]."'";
                    $comma=',';
                }
                $sqls.=");nnn";
            }
        }
        $backfilepath=$this->dataDir.date("Ymdhis",time()).'.sql';
       
        //写入文件
        $filehandle = fopen($backfilepath, "w");
        fwrite($filehandle, $sqls);
        fclose($filehandle);
    }
    private function delarray($array){    //处理传入进来的数组
        foreach($array as $tables){
            if($tables=='*'){    //所有的表(获得表名时不能按常规方式来组成一个数组)
                $newtables=mysql_list_tables($this->dbName,$this->mysql_link);
                $tableList = array();
                for ($i = 0; $i < mysql_numrows($newtables); $i++){
                    array_push($tableList,mysql_tablename($newtables, $i));
                }
                $tableList=$tableList;
            }else{
                $tableList=$array;
                break;
            }
        }
        return $tableList;
    }
}
?>

$rs0 = $pdo->exec($sql);
$pre = $pdo->prepare($sql);
$rs1 = $pre->execute();

define('DB_NAME','test');
define('DB_USER','test');
define('DB_PASSWD','test');
define('DB_HOST','localhost');
define('DB_TYPE','mysql');
$dbh = new PDO(DB_TYPE.':host='.DB_HOST.';dbname='.DB_NAME, DB_USER, DB_PASSWD);

$sql = 'select * from test';
foreach ( $dbh->query($sql) as $value)
{
    echo $value[col];
};

$sth = $dbh->prepare('update db set zh_CN= :str where SN=:SN');
$sth->bindParam(':str',$str,PDO::PARAM_STR,12);
$sth->bindParam(':SN',$SN);
$sth->execute();

$sth = $dbh->prepare('insert into db ("zh_CN","zh_TW")values(:str , :SN');
foreach ($array => $value )
{
 $sth->bindParam(':str',$value[str],PDO::PARAM_STR,12);
 $sth->bindParam(':SN',$value[SN]);
 $sth->execute();
}

$sth = $dbh->prepare('select * from db where SN = :SN');
$sth->bindParam(':SN',$value[SN]);
$sth->execute();
while($meta = $sth->fetch(PDO::FETCH_ASSOC))
{
 echo $meta["name"];
}

$sth = $dbh->prepare('select * from db where SN = :SN');
$sth->bindParam(':SN',$value[SN]);
$sth->execute();
if ($sth->errorCode())
{
 echo "有错误！有错误！";
 print_r($sth->errorInfo());
}