php实现mysql数据库备份类

1、实例化DbBak需要告诉它两件事：数据服务器在哪里($connectid)、备份到哪个目录($backupDir)：

require_once('DbBak.php');
require_once('TableBak.php');
$connectid = mysql_connect('localhost','root','123456');
$backupDir = 'data';
$DbBak = new DbBak($connectid,$backupDir);

2、然后就可以开始备份数据库了，你不仅能够指定备份那个数据库，而且能详细设置只备份那几个表：
2.1如果你想备份mybbs库中的所有表，只要这样：

$DbBak->backupDb('mybbs');

2.2如果你只想备份mybbs库中的board、face、friendlist表，可以用一个一维数组指定：

$DbBak->backupDb('mybbs',array('board','face','friendsite'));

2.3如果只想备份一个表，比如board表：
$DbBak->backupDb('mybbs','board');
3，数据恢复：
对于2.1、2.1、2.3三种情况，只要相应的修改下语句，把backupDb换成restoreDb就能实现数据恢复了：

$DbBak->restoreDb('mybbs');
SQL代码
$DbBak->restoreDb('mybbs',array('board','face','friendsite'));
PHP代码
$DbBak->restoreDb('mybbs','board');
PHP代码
require_once('TableBak.php');
class DbBak {
var $_mysql_link_id;
var $_dataDir;
var $_tableList;
var $_TableBak;

function DbBak($_mysql_link_id,$dataDir)
{
( (!is_string($dataDir)) || strlen($dataDir)==0) && die('error:$datadir is not a string');
!is_dir($dataDir) && mkdir($dataDir);
$this->_dataDir = $dataDir;
$this->_mysql_link_id = $_mysql_link_id;
}

function backupDb($dbName,$tableName=null)
{
( (!is_string($dbName)) || strlen($dbName)==0 ) && die('$dbName must be a string value');
//step1:选择数据库：
mysql_select_db($dbName);
//step2:创建数据库备份目录
$dbDir = $this->_dataDir.DIRECTORY_SEPARATOR.$dbName;
!is_dir($dbDir) && mkdir($dbDir);
//step3:得到数据库所有表名 并开始备份表
$this->_TableBak = new TableBak($this->_mysql_link_id,$dbDir);
if(is_null($tableName)){//backup all table in the db
$this->_backupAllTable($dbName);
return;
}
if(is_string($tableName)){
(strlen($tableName)==0) && die('....');
$this->_backupOneTable($dbName,$tableName);
return;
}
if (is_array($tableName)){
foreach ($tableName as $table){
( (!is_string($table)) || strlen($table)==0 ) && die('....');
}
$this->_backupSomeTalbe($dbName,$tableName);
return;
}
}

function restoreDb($dbName,$tableName=null){
( (!is_string($dbName)) || strlen($dbName)==0 ) && die('$dbName must be a string value');
//step1:检查是否存在数据库 并连接：
@mysql_select_db($dbName) || die("the database <b>$dbName</b> dose not exists");
//step2:检查是否存在数据库备份目录
$dbDir = $this->_dataDir.DIRECTORY_SEPARATOR.$dbName;
!is_dir($dbDir) && die("$dbDir not exists");
//step3:start restore
$this->_TableBak = new TableBak($this->_mysql_link_id,$dbDir);
if(is_null($tableName)){//backup all table in the db
$this->_restoreAllTable($dbName);
return;
}
if(is_string($tableName)){
(strlen($tableName)==0) && die('....');
$this->_restoreOneTable($dbName,$tableName);
return;
}
if (is_array($tableName)){
foreach ($tableName as $table){
( (!is_string($table)) || strlen($table)==0 ) && die('....');
}
$this->_restoreSomeTalbe($dbName,$tableName);
return;
}
}

function _getTableList($dbName)
{
$tableList = array();
$result=mysql_list_tables($dbName,$this->_mysql_link_id);
for ($i = 0; $i < mysql_num_rows($result); $i++){
array_push($tableList,mysql_tablename($result, $i));
}
mysql_free_result($result);
return $tableList;
}

function _backupAllTable($dbName)
{
foreach ($this->_getTableList($dbName) as $tableName){
$this->_TableBak->backupTable($tableName);
}
}

function _backupOneTable($dbName,$tableName)
{
!in_array($tableName,$this->_getTableList($dbName)) && die("指定的表名<b>$tableName</b>在数据库中不存在");
$this->_TableBak->backupTable($tableName);
}

function _backupSomeTalbe($dbName,$TableNameList)
{
foreach ($TableNameList as $tableName){
!in_array($tableName,$this->_getTableList($dbName)) && die("指定的表名<b>$tableName</b>在数据库中不存在");
}
foreach ($TableNameList as $tableName){
$this->_TableBak->backupTable($tableName);
}
}

function _restoreAllTable($dbName)
{
//step1:检查是否存在所有数据表的备份文件 以及是否可写：
foreach ($this->_getTableList($dbName) as $tableName){
$tableBakFile = $this->_dataDir.DIRECTORY_SEPARATOR
. $dbName.DIRECTORY_SEPARATOR
. $tableName.DIRECTORY_SEPARATOR
. $tableName.'.sql';
!is_writeable ($tableBakFile) && die("$tableBakFile not exists or unwirteable");
}
//step2:start restore
foreach ($this->_getTableList($dbName) as $tableName){
$tableBakFile = $this->_dataDir.DIRECTORY_SEPARATOR
. $dbName.DIRECTORY_SEPARATOR
. $tableName.DIRECTORY_SEPARATOR
. $tableName.'.sql';
$this->_TableBak->restoreTable($tableName,$tableBakFile);
}
}

function _restoreOneTable($dbName,$tableName)
{
//step1:检查是否存在数据表:
!in_array($tableName,$this->_getTableList($dbName)) && die("指定的表名<b>$tableName</b>在数据库中不存在");
//step2:检查是否存在数据表备份文件 以及是否可写：
$tableBakFile = $this->_dataDir.DIRECTORY_SEPARATOR
. $dbName.DIRECTORY_SEPARATOR
. $tableName.DIRECTORY_SEPARATOR
. $tableName.'.sql';
!is_writeable ($tableBakFile) && die("$tableBakFile not exists or unwirteable");
//step3:start restore
$this->_TableBak->restoreTable($tableName,$tableBakFile);
}
function _restoreSomeTalbe($dbName,$TableNameList)
{
//step1:检查是否存在数据表:
foreach ($TableNameList as $tableName){
!in_array($tableName,$this->_getTableList($dbName)) && die("指定的表名<b>$tableName</b>在数据库中不存在");
}
//step2:检查是否存在数据表备份文件 以及是否可写：
foreach ($TableNameList as $tableName){
$tableBakFile = $this->_dataDir.DIRECTORY_SEPARATOR
. $dbName.DIRECTORY_SEPARATOR
. $tableName.DIRECTORY_SEPARATOR
. $tableName.'.sql';
!is_writeable ($tableBakFile) && die("$tableBakFile not exists or unwirteable");
}
//step3:start restore:
foreach ($TableNameList as $tableName){
$tableBakFile = $this->_dataDir.DIRECTORY_SEPARATOR
. $dbName.DIRECTORY_SEPARATOR
. $tableName.DIRECTORY_SEPARATOR
. $tableName.'.sql';
$this->_TableBak->restoreTable($tableName,$tableBakFile);
}
}
}
?>

<?php      
//只有DbBak才能调用这个类      
class TableBak{      
var $_mysql_link_id;      
var $_dbDir;      
//private $_DbManager;      
function TableBak($mysql_link_id,$dbDir)      
{      
$this->_mysql_link_id = $mysql_link_id;      
$this->_dbDir = $dbDir;      
}      

function backupTable($tableName)      
{      
//step1:创建表的备份目录名：      
$tableDir = $this->_dbDir.DIRECTORY_SEPARATOR.$tableName;      
!is_dir($tableDir) && mkdir($tableDir);      
//step2:开始备份：      
$this->_backupTable($tableName,$tableDir);      
}      

function restoreTable($tableName,$tableBakFile)      
{      
set_time_limit(0);      
$fileArray = @file($tableBakFile) or die("can open file $tableBakFile");      
$num = count($fileArray);      
mysql_unbuffered_query("DELETE FROM $tableName");      
$sql = $fileArray[0];      
for ($i=1;$i<$num-1;$i++){       
mysql_unbuffered_query($sql.$fileArray[$i]) or (die (mysql_error()));      
}      
return true;      
}      

function _getFieldInfo($tableName){      
$fieldInfo = array();      
$sql="SELECT * FROM $tableName LIMIT 1";      
$result = mysql_query($sql,$this->_mysql_link_id);      
$num_field=mysql_num_fields($result);      
for($i=0;$i<$num_field;$i++){      
$field_name=mysql_field_name($result,$i);      
$field_type=mysql_field_type($result,$i);      
$fieldInfo[$field_name] = $field_type;      
}      
mysql_free_result($result);      
return $fieldInfo;      
}      
function _quoteRow($fieldInfo,$row){      
foreach ($row as $field_name=>$field_value){      
$field_value=strval($field_value);      
switch($fieldInfo[$field_name]){        
case "blob":     $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;          
case "string": $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;        
case "date":     $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;        
case "datetime": $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;        
case "time":     $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;        
case "unknown":   $row[$field_name] = "'".mysql_escape_string($field_value)."'";break;          
case "int":     $row[$field_name] = intval($field_value); break;      
case "real":     $row[$field_name] = intval($field_value); break;      
case "timestamp":$row[$field_name] = intval($field_value); break;      
default:     $row[$field_name] = intval($field_value); break;      
}      
}      
return $row;      
}      
function _backupTable($tableName,$tableDir)      
{      
//取得表的字段类型：      
$fieldInfo = $this->_getFieldInfo($tableName);      

//step1:构造INSERT语句前半部分 并写入文件：      
$fields = array_keys($fieldInfo);      
$fields = implode(',',$fields);      
$sqltext="INSERT INTO $tableName($fields)VALUES \r\n";      
$datafile = $tableDir.DIRECTORY_SEPARATOR.$tableName.'.sql';      
(!$handle = fopen($datafile,'w')) && die("can not open file <b>$datafile</b>");      
(!fwrite($handle, $sqltext))   && die("can not write data to file <b>$datafile</b>");      
fclose($handle);      

//step2:取得数据 并写入文件：      
//取出表资源：      
set_time_limit(0);      
$sql = "select * from $tableName";      
$result = mysql_query($sql,$this->_mysql_link_id);      
//打开数据备份文件:$tableName.xml      
$datafile = $tableDir.DIRECTORY_SEPARATOR.$tableName.'.sql';      
(!$handle = fopen($datafile,'a')) && die("can not open file <b>$datafile</b>");      
//逐条取得表记录并写入文件：      
while ($row = mysql_fetch_assoc($result)) {      
$row = $this->_quoteRow($fieldInfo,$row);       
$record='(' . implode(',',$row) . ");\r\n";      
(!fwrite($handle, $record))   && die("can not write data to file <b>$datafile</b>");      
}      
mysql_free_result($result);      
//关闭文件：      
fclose($handle);      

return true;      
}      

}      
?>

备份mybbs数据库：

SQL代码
//example 1 backup:
require_once('DbBak.php');
require_once('TableBak.php');
$connectid = mysql_connect('localhost','root','123456');
$backupDir = 'data';
$DbBak = new DbBak($connectid,$backupDir);
$DbBak->backupDb('mybbs');

恢复mybbs数据库：

require_once('DbBak.php');      
require_once('TableBak.php');      
$connectid = mysql_connect('localhost','root','123456');      
$backupDir = 'data';      
$DbBak = new DbBak($connectid,$backupDir);      
$DbBak->restoreDb('mybbs');