本文章提供了二款數據庫教程連接實例，主要是講php教程 mysql教程數據相關操作，有需要的朋友可以使用看看。
<?php
class mysql {
private $db_host; //主機地址
private $db_user; //用戶名
private $db_pass; //連接密碼
private $db_name; //名稱
private $db_charset; //編碼
private $conn;
public $debug=false;//調試開關，默認關閉
private $query_id; //用於判斷sql語句是否執行成功
private $result; //結果集
private $num_rows; //結果集中行的數目，僅對select有效
private $insert_id; //上一步 insert 操作產生的 id
// 構造/析構函數
function __construct ($db_host,$db_user,$db_pass,$db_name,$db_charset,$conn) {
$this->db_host = $db_host ;
$this->db_user = $db_user ;
$this->db_pass = $db_pass ;
$this->db_name = $db_name ;
$this->db_charset = $db_charset ;
$this->conn = $conn ;
$this->connect();
}
function __destruct () {
@mysql_close($this->conn);
}
// 連接/選擇數據庫
public function connect () {
if ($this->conn == 'pconn') {
@$this->conn = mysql_pconnect($this->db_host,$this->db_user,$this->db_pass);
} else {
@$this->conn = mysql_connect($this->db_host,$this->db_user,$this->db_pass);
}
if (!$this->conn) {
$this->show_error('數據庫-連接失敗：用戶名或密碼錯誤！');
}
if (!@mysql_select_db($this->db_name,$this->conn)) {
$this->show_error("數據庫-選擇失敗：數據庫 $this->db_name 不可用");
}
mysql_query("set names $this->db_charset");
return $this->conn;
}
// query方法
public function query ($sql) {
if ($this->query_id) $this->free_result();
$this->query_id = @mysql_query($sql,$this->conn);
if (!$this->query_id) $this->show_error("sql語句 <b>"$sql"</b> 執行時遇到錯誤");
return $this->query_id;
}
// 顯示詳細錯誤信息
public function show_error ($msg) {
if($this->debug){
$errinfo = mysql_error();
echo "錯誤：$msg <br/> 返回：$errinfo<p>";
}else{
echo '<p>出現錯誤！<p>';
}
}
// 獲得query執行成功與否的信息
public function get_query_info($info){
if ($this->query_id) {
echo $info;
}
}
// 查詢所有
public function findall ($table_name) {
$this->query("select * from $table_name");
}
// mysql_fetch_array
public function fetch_array () {
if ($this->query_id) {
$this->result = mysql_fetch_array($this->query_id);
return $this->result;
}
}
// ......
public function fetch_assoc () {
if ($this->query_id) {
$this->result = mysql_fetch_assoc($this->query_id);
return $this->result;
}
}
public function fetch_row () {
if ($this->query_id) {
$this->result = mysql_fetch_row($this->query_id);
return $this->result;
}
}
public function fetch_object () {
if ($this->query_id) {
$this->result = mysql_fetch_object($this->query_id);
return $this->result;
}
}
// 獲取 num_rows
public function num_rows () {
if ($this->query_id) {
$this->num_rows = mysql_num_rows($this->query_id);
return $this->num_rows;
}
}
// 獲取 insert_id
public function insert_id () {
return $this->insert_id = mysql_insert_id();
}
// 顯示共有多少張表
public function show_tables () {
$this->query("show tables");
if ($this->query_id) {
echo "數據庫 $this->db_name 共有 ".$this->num_rows($this->query_id)." 張表<br/>";
$i = 1;
while ($row = $this->fetch_array($this->query_id)){
echo "$i -- $row[0]<br/>";
$i ++;
}
}
}
// 顯示共有多少個數據庫
public function show_dbs(){
$this->query("show databases");
if ($this->query_id) {
echo "共有數據庫 ".$this->num_rows($this->query_id)." 個<br/>";
$i = 1;
while ($this->row = $this->fetch_array($this->query_id)){
echo "$i -- ".$this->row[database]."<br />";
$i ++;
}
}
}
// 刪除數據庫：返回刪除結果
public function drop_db ($db_name='') {
if ($db_name == '') {
$db_name = $this->db_name;//默認刪除當前數據庫
$this->query("drop database $db_name");
}else {
$this->query("drop database $db_name");
}
if ($this->query_id) {
return "數據庫 $db_name 刪除成功";
}else {
$this->show_error("數據庫 $db_name 刪除失敗");
}
}
// 刪除數據表：返回刪除結果
public function drop_table ($table_name) {
$this->query("drop table $table_name");
if ($this->query_id) {
return "數據表 $table_name 刪除成功";
}else {
$this->show_error("數據表 $table_name 刪除失敗");
}
}
// 創建數據庫
public function create_db ($db_name) {
$this->query("create database $db_name");
if($this->query_id){
return "數據庫 $db_name 創建成功";
}else {
$this->show_error("數據庫 $db_name 創建失敗");
}
}
// 獲取數據庫版本
public function get_info(){
echo mysql_get_server_info();
}
// 釋放內存
public function free_result () {
if ( @mysql_free_result($this->query_id) )
unset ($this->result);
$this->query_id = 0;
}
} // end class
?>
下面提供一款自動選擇數據庫遠程或本地連接代碼
<?php
// 包含mysql操作類
include_once 'mysql.class.php';
// 本地mysql數據
$mysql_local_data = array('db_host'=>'localhost',
'db_user'=>'root',
'db_pass'=>'root',
'db_name'=>'test');
// 遠程mysql數據
$mysql_remote_data = array('db_host'=>'61.183.41.178',
'db_user'=>'xxx',
'db_pass'=>'xxx',
'db_name'=>'xxx');
// 公用數據
$tb_prefix = 'php95_';
$db_charset = 'utf-8';
//本地連接成功則實例化本地mysql類，否則連接遠程數據庫並實例化mysql類
if (@mysql_connect($mysql_local_data[db_host], $mysql_local_data[db_user], $mysql_local_data[db_pass]))
$db = new mysql($db_host, $mysql_local_data[db_user], $mysql_local_data[db_pass], $mysql_local_data[db_name], $db_charset, $conn);
else
$db = new mysql($mysql_remote_data[db_host], $mysql_remote_data[db_user], $mysql_remote_data[db_pass], $mysql_remote_data[db_name], $db_charset, $conn);
$db->show_tables(); //測試：顯示當前數據庫下的所有表名
?>
假設我們要在test.php文件中操作虛擬主機的數據庫，則首先要在本地調試，那麼必然要連接本地、遠程兩個不同的數據庫，問題：怎麼讓test.php自動識別當下該連接本地還是遠程數據庫呢？
