php+mysqli实现批量替换数据库表前缀的方法

<?php 
header ( 'http-equiv="Content-Type" content="text/html; charset=utf-8"' ); 
$DB_host = "localhost"; //数据库主机 
$DB_user = "root"; //数据库用户 
$DB_psw = "root3306"; //数据库密码 
$DB_datebase = "gk_yue39_com"; //数据库名 
$DB_charset = "utf8"; //数据库字符集 
$dbprefix="yue392_com_"; 
$new_dbprefix="yue39_com_"; 
$db = new mysqli ( $DB_host, $DB_user, $DB_psw ); //实例化对象 
 
//检查连接 
if (mysqli_connect_errno ()) { 
 printf ( "Connect failed: %sn", mysqli_connect_error () ); 
 exit (); 
} 
 
$db->select_db ( $DB_datebase ); //选择操作数据库 
 
$db->set_charset ( $DB_charset ); //设置数据库字符集 
 
//执行一个查询 
$sql = 'show tables'; 
$result = $db->query ( $sql ); 
 
echo $result->num_rows . ' 行结果  ' . $result->field_count . ' 列内容<br/>'; 
 
//$result->data_seek('5');//从结果集中第5条开始取结果 
 
echo '<table border="1" cellspacing="0" cellpadding="0" align="center" width="90%">'; 
 
//循环输出字段名 
//$result->field_seek(2);//从字段集中第2条开始取结果 
while ( true == ($field = $result->fetch_field ()) ) { 
 echo '<th>' . $result->current_field . '_' . $field->name . '(' . $field->length . ')</th>'; 
} 
 
//循环输出查询结果 
while ( true == ($row = $result->fetch_assoc ()) ) { 
 echo '<tr>'; 
 foreach ( $row as $col ) { 
$sql="rename table `".$col."` to `".str_replace ( $dbprefix, $new_dbprefix, $col)."`"; 
    if($db->query ( $sql )){ 
  echo '<td align="center">' . $sql. '</td><td><font color="blue"> success</font></td>'; 
  }else{ 
  echo '<td align="center">' . $sql. '</td><td><font color="red"> failed</font></td>';
  }  
  } 
 echo '</tr>'; 
} 
 
echo '</table>'; 
$result->free ();//释放结果集 
$db->close (); //关闭连接 
?>