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本文章主要是介绍关于用php对mysql数据库,与数据表以及数据进行备份了,代码写得有一点长不过行行都是实例了,好了费话不说多了我们来看看这款mysql数据库备份代码的吧。

这个程序仅仅备份和恢复数据,使用方法很简单,实例化DbBak,然后调用bakupDb和restoreDb方法:
   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");
//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 rn";
                $datafile = $tableDir.DIRECTORY_SEPARATOR.$tableName.".sql";
                (!$handle = fopen($datafile,"w")) && die("can not open file $datafile");
                (!fwrite($handle, $sqltext))  && die("can not write data to file $datafile");
                fclose($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 $datafile");
                //逐条取得表记录并写入文件:
                while ($row = mysql_fetch_assoc($result)) {
                        $row = $this->_quoteRow($fieldInfo,$row);       
                        $record="(" . implode(",",$row) . ");rn";
                        (!fwrite($handle, $record))  && die("can not write data to file $datafile");
                }
                mysql_free_result($result);
                //关闭文件:
                fclose($handle);
               
                return true;
        }

}
?>
require_once("TableBak.php");
这个文件代码

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 $dbName 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($dbName)) && die("指定的表名$tableName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$tableName在数据库中不存在");
                }
                foreach ($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($dbName)) && die("指定的表名$tableName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$tableName在数据库中不存在");
                }
                //step2:检查是否存在数据表备份文件 以及是否可写:
                foreach ($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);
                }
        }
}
?>


$connectid = mysql_connect("localhost","root","123456");

$backupDir = "data";

$DbBak = new DbBak($connectid,$backupDir);
复制代码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");
复制代码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"));
复制代码2.3如果只想备份一个表,比如board表: $DbBak->backupDb("mybbs","board");
复制代码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: $DbBak->restoreDb("mybbs");
复制代码$DbBak->restoreDb("mybbs",array("board","face","friendsite"));
复制代码$DbBak->restoreDb("mybbs","board");


测试实例

//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");

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

本文来源:http://www.gdgbn.com/shujuku/20384/