为什么我的数据库连接总是超限？

[梦幻山河]

我的网站(php+mysql)放在虚拟主机上：总是出现连接超限制？
提示如下错误：
Warning: mysql_connect(): Host 'shlt-2.etianxia.com' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts' in D:\customer\htdocs\whthgg\inc\db_mysql.inc.php on line 84
Database error: connect(203.212.5.188, sq_whthggcom, $Password) failed.
MySQL Error: ()
Session halted.

空间提供商说我的程序有问题，连接数据后，没有关闭！我认为这不是一个合适的理由，页面打开后，数据库自动关闭啊，
况且我还写了关闭数据库的代码,

[梦幻山河]

连接数据文件：db_mysql.inc.php的代码：
<?php
/*
* Session Management for PHP3
*
* Copyright (c) 1998-2000 NetUSE AG
* Boris Erdmann, Kristian Koehntopp
*
* $Id: db_mysql.inc,v 1.8 2001/10/12 16:16:16 layne_weathers Exp $
*
* Modified by cnet on 2002/08/02
* Removed vars:$Seq_Table
* Removed functions:next_id() metadata()
* Changed fuctions:db_sql(),query()
* Added vars: Explains
* Added function:query_first($string),insert_id();
*/
class DB_Sql {

/* public: connection parameters */
var $Host;
var $Database;
var $User;
var $Password;

/* public: configuration parameters */
var $Auto_Free = 1; ## Set to 1 for automatic mysql_free_result()
var $Debug = 0; ## Set to 1 for debugging messages.
var $Explains = 0; ## Set to 1 for explaining Query strings messages;
var $Halt_On_Error = "yes"; ## "yes" (halt with message), "no" (ignore errors quietly), "report" (ignore errror, but spit a warning)
//var $Seq_Table = "db_sequence"; ##used in next_id()

/* public: result array and current row number */
var $Record = array();
var $Row;

/* public: current error number and error text */
var $Errno = 0;
var $Error = "";

/* public: this is an api revision, not a CVS revision. */
var $type = "mysql";
var $revision = "1.2";

/* private: link and query handles */
var $Link_ID = 0;
var $Query_ID = 0;



/* public: constructor */
function DB_Sql($query = "") {
global $sys_vars;// should be set in config.php
$this->Host = $sys_vars['Host'];
$this->Database = $sys_vars['Database'];
$this->User = $sys_vars['dbuser'];
$this->Password = $sys_vars['dbpass'];
$this->query($query);
}

/* public: some trivial reporting */
function link_id() {
return $this->Link_ID;
}

function Query_ID() {
return $this->Query_ID;
}

/* public: connection management */
function connect($Database = "", $Host = "", $User = "", $Password = "") {
/* Handle defaults */
if ("" == $Database)
$Database = $this->Database;
if ("" == $Host)
$Host = $this->Host;
if ("" == $User)
$User = $this->User;
if ("" == $Password)
$Password = $this->Password;

/* establish connection, select database */
if ( 0 == $this->Link_ID ) {

$this->Link_ID=mysql_connect($Host, $User, $Password);//?mysql_pconnect
if (!$this->Link_ID) {
$this->halt("connect($Host, $User, \$Password) failed.");//?mysql_pconnect
return 0;
}

if (!@mysql_select_db($Database,$this->Link_ID)) {
$this->halt("cannot use database ".$Database);
return 0;
}
}
return $this->Link_ID;
mysql_close();
}

/* public: discard the query result */
function free() {
@mysql_free_result($this->Query_ID);
$this->Query_ID = 0;
}
/* public: return the last insert id */
function insert_id() {
return mysql_insert_id($this->Link_ID);
}
/* public: perform a query */
function query($Query_String) {

global $query_count;

/* No empty queries, please, since PHP4 chokes on them. */
if ($Query_String == "")
/* The empty query string is passed on from the constructor,
* when calling the class without a query, e.g. in situations
* like these: '$db = new DB_Sql_Subclass;'
*/
return 0;

if (!$this->connect()) {
return 0; /* we already complained in connect() about that. */
};

# New query, discard previous result.
if ($this->Query_ID) {
$this->free();
}
######################### Experimetal Code START###########################################
if ($this->Debug)
{
global $pagestarttime,$querytime,$DebugMode; //should be defined in header file
if($DebugMode)
ob_end_clean();
echo "<pre>";
printf("Debug: query = %s<br>\n", $Query_String);
$pageendtime = microtime();
$starttime = explode(" ",$pagestarttime);
$endtime = explode(" ",$pageendtime);

$beforetime = $endtime[0] - $starttime[0] + $endtime[1] - $starttime[1];
echo "Time before: $beforetime\n";
}

$query_count ++; // count the number of queries
######################### Experimetal Code END###########################################

$this->Query_ID = @mysql_query($Query_String,$this->Link_ID);
$this->Row = 0;
$this->Errno = mysql_errno();
$this->Error = mysql_error();
if (!$this->Query_ID) {
$this->halt("Invalid SQL: ".$Query_String);
}
######################### Experimetal Code START###########################################
if ($this->Debug)
{
$pageendtime = microtime();
$starttime = explode(" ",$pagestarttime);
$endtime = explode(" ",$pageendtime);

$aftertime = $endtime[0] - $starttime[0] + $endtime[1] - $starttime[1];
$querytime += $aftertime - $beforetime;
echo "Time after: $aftertime\n";
echo "</pre>\n";
if (($this->Explains) && substr(trim(strtoupper($Query_String)),0,6)=="SELECT")
{
$explain_id = mysql_query("EXPLAIN $Query_String",$this->Link_ID);
echo "
<table width=100% border=1 cellpadding=2 cellspacing=1>
<tr>
<td><b>table</b></td>
<td><b>type</b></td>
<td><b>possible_keys</b></td>
<td><b>key</b></td>
<td><b>key_len</b></td>
<td><b>ref</b></td>
<td><b>rows</b></td>
<td><b>Extra</b></td>
</tr>\n";
while($array=mysql_fetch_array($explain_id))
{
echo "
<tr>
<td>$array[table] </td>
<td>$array[type] </td>
<td>$array[possible_keys] </td>
<td>$array[key] </td>
<td>$array[key_len] </td>
<td>$array[ref] </td>
<td>$array[rows] </td>
<td>$array[Extra] </td>
</tr>\n";
}
echo "</table>\n<BR><hr>\n";
}
if($DebugMode) ob_start();
}
######################### Experimetal Code END###########################################

# Will return nada if it fails. That's fine.
return $this->Query_ID;
}

/* public: walk result set */
function next_record() {
if (!$this->Query_ID) {
$this->halt("next_record called with no query pending.");
return 0;
}

$this->Record = @mysql_fetch_array($this->Query_ID);
$this->Row += 1;
$this->Errno = mysql_errno();
$this->Error = mysql_error();

$stat = is_array($this->Record);
if (!$stat && $this->Auto_Free) {
$this->free();
}
return $stat;
}

[梦幻山河]

/* added by cnet:// does a query,return the first row free the result */
function query_first($query_string)
{
$this->query($query_string);
if (!$this->Query_ID) {
$this->halt("Invalid query id (".$this->Query_ID.") on this query: $query_string");
return 0;
}
$this->Record = @mysql_fetch_array($this->Query_ID);
$this->Errno = mysql_errno();
$this->Error = mysql_error();
$this->free();
return $this->Record;
}

/* public: position in result set */
function seek($pos = 0) {
$status = @mysql_data_seek($this->Query_ID, $pos);
if ($status)
$this->Row = $pos;
else {
$this->halt("seek($pos) failed: result has ".$this->num_rows()." rows.");

/* half assed attempt to save the day,
* but do not consider this documented or even
* desireable behaviour.
*/
@mysql_data_seek($this->Query_ID, $this->num_rows());
$this->Row = $this->num_rows();
return 0;
}
return 1;
}

/* public: table locking */
function lock($table, $mode = "write") {
$query = "lock tables ";
if (is_array($table)) {
while (list($key,$value) = each($table)) {
if (!is_int($key)) {
// texts key are "read", "read local", "write", "low priority write"
$query .= "$value $key, ";
} else {
$query .= "$value $mode, ";
}
}
$query = substr($query,0,-2);
} else {
$query .= "$table $mode";
}
$res = $this->query($query);
if (!$res) {
$this->halt("lock() failed.");
return 0;
}
return $res;
}

function unlock() {
$res = $this->query("unlock tables");
if (!$res) {
$this->halt("unlock() failed.");
}
return $res;
}

/* public: evaluate the result (size, width) */
function affected_rows() {
return @mysql_affected_rows($this->Link_ID);
}

function num_rows() {
return @mysql_num_rows($this->Query_ID);
}

function num_fields() {
return @mysql_num_fields($this->Query_ID);
}

/* public: shorthand notation */
function nf() {
return $this->num_rows();
}

function np() {
print $this->num_rows();
}

function f($Name) {
if (isset($this->Record[$Name])) {
return $this->Record[$Name];
}
}

function p($Name) {
if (isset($this->Record[$Name])) {
print $this->Record[$Name];
}
}
/* private: error handling */
function halt($msg) {
$this->Error = @mysql_error($this->Link_ID);
$this->Errno = @mysql_errno($this->Link_ID);
if ($this->Halt_On_Error == "no")
return;

$this->haltmsg($msg);

if ($this->Halt_On_Error != "report")
die("Session halted.");
}

function haltmsg($msg) {
printf("<b>Database error:</b> %s<br>\n", $msg);
printf("<b>MySQL Error</b>: %s (%s)<br>\n",
$this->Errno,
$this->Error);
}
}
?>

[梦幻山河]

我写的代码：
<?
include "inc/header.inc.php";
include "inc/db_mysql.inc.php";
include "inc/func.inc.php";

if (!$_SESSION['admin']){
header("Location: admin_index.php");
}

$db = new db_sql();

if ($title && $Content){
$title = text_decode($title);


$db -> query("insert into news (type,title,content,time) values($type,'$title','$Content',".time().")");

$id = $db -> insert_id();

if ($upfile_name && $id){
if (($upfile_type=="image/gif") || ($upfile_type=="image/pjpeg") || ($upfile_type=="image/x-png")){

if ($upfile_type=="image/gif"){
$type = ".gif";
}
elseif ($upfile_type=="image/pjpeg"){
$type=".jpg";
}
elseif ($upfile_type=="image/x-png"){
$type=".png";
}

$newfilename = date("YmdHis").$type;
if ((!file_exists("pic/".date("Ym")."/"))&&(!is_dir("pic/".date("Ym")."/"))){
mkdir("pic/".date("Ym")."/",0771);
}//创建档案文件夹
$filename = "pic/".date("Ym")."/".$newfilename;

// 将文件存放到服务器
if (copy($upfile,$filename)){

$db -> query("update news set pic='$filename' where newsid='$id'");
}
else{
echo "<script language=javascript>
<!--
alert('图片上传失败！')
-->
</script>";
echo "<script language=javascript>
<!--
history.back()
-->
</script>";
}
}
else{
echo "<script language=javascript>
<!--
alert('不是有效的可显示图片文件！')
-->
</script>";
echo "<script language=javascript>
<!--
history.back()
-->
</script>";
}
}

header("Location: admin_news6.php");
}
?>
这样有问题吗？

[causky]

这个错误,是因为mysql最大错误连接数吃满了
1. 可能是因为别人网站错误连接太多
2. 建议在完成操作之后,进行mysql_close操作.虽然PHP会自己释放
3. 要求服务商,把mysql允许的最大错误数调到很高,这个不能根本解决问题
4. 由于网络状况不佳造成的错误连接过多[最有可能]