取得系统中的数据库类型

function getBbsCharset($table){
global $dbhost,$dbuser,$dbpw,$dbname;
mysql_connect($dbhost,$dbuser,$dbpw);
if( mysql_get_server_info() < '4.1' ){
return ;
}
mysql_select_db($dbname);
$query=@mysql_query("SHOW CREATE TABLE $table");
if(!$query){
return ;
}
while($rs=mysql_fetch_array($query)){
$table=$rs['Create Table'];
}
$table=preg_replace("/(.*)DEFAULT CHARSET=([a-z0-9]+)(.*)/is","//2",$table);
return $table;
}