几种常用PHP连接数据库的代码示例

PHP连接数据库之PHP连接MYSQL数据库代码

< ?php   

$mysql_server_name='localhost' 

//改成自己的mysql数据库服务器  

$mysql_username='root' 

//改成自己的mysql数据库用户名  

$mysql_password='12345678' 

//改成自己的mysql数据库密码  

$mysql_database='mycounter'

 //改成自己的mysql数据库名  

$conn=mysql_connect($mysql_server_name,

$mysql_username,$mysql_password,

$mysql_database)   

$sql='CREATE DATABASE mycounter 

DEFAULT CHARACTER SET gbk COLLATE gbk_chinese_ci   

'   

mysql_query($sql)   

$sql='CREATE TABLE `counter` 

(`id` INT(255) UNSIGNED NOT NULL 

AUTO_INCREMENT ,`count` INT(255) 

UNSIGNED NOT NULL DEFAULT 0,PRIMARY KEY 

( `id` ) ) TYPE = innodb'   

mysql_select_db($mysql_database,$conn)   

$result=mysql_query($sql)   

//echo $sql   

mysql_close($conn)   

echo "Hello!数据库mycounter已经成功建立！"   

?> 

PHP连接数据库之PHP连接ACCESS数据库代码方法

< ?  

$conn = new com("ADODB.Connection")   

$connstr = "DRIVER={Microsoft

 Access Driver (*.mdb)} 

DBQ=". realpath("data/db.mdb")   

$conn->Open($connstr)   

$rs = new com("ADODB.RecordSet")   

$rs->Open("select *

 from szd_t",$conn,1,1)   

while(! $rs->eof) {   

$f = $rs->Fields(1)   

echo $f->value   

$rs->MoveNext()   

}   

?>

数据库有很多种类：mysql，oracle，mssql，db2等等。PHP *** 作数据库的时候，要保证该类型数据库的扩展已开启。这里连接的数据库以mysql为例：<?php

//数据库服务器地址

$host="localhost"

//连接数据库用户名

$uname="root"

//连接数据库密码

$upass=""

//连接数据库

$conn=mysql_connect($host, $uname,$upass)

//判断连接

if(!$conn){

die("连接数据库失败！").mysql_errno()

}

//连接成功，其他 *** 作省略

?>

我也刚刚学PHP，正在研究中，虽然你只给10分........

首先，将代码保存到一个文件，如：mysql.class.php

其次，在一个常用的文件里调用：比如头部文件header.php,因为我放在根目录所以用下面方式导入其他文件：

require dirname(__FILE__) . 'include/config.php'

//导入类文件

require dirname(__FILE__) . 'include/mysql.class.php'

//定义一个类及初始化数据库类

$db = new mysql($db_host, $db_user, $db_pass, $db_name)

$db_host = $db_user = $db_pass = $db_name = NULL

然后，在test.php文件调用：

require_once dirname(__FILE__) . '/header.php'

使用方法：

$sql = "读取表"

$res = $db->query($sql)

$info = array()//定义数组

while($row=$db->fetchRow($res))

{

$arr['id'] = $row['id']

$arr['title'] = $row['title']

$info[] = $arr

}

可以在显示的地方用：

foreach($info as $i)

{

echo $i['title']."<br />"

}

或是直接使用while

还用另一种调用方式：

$here_area = $db->getRow("select areaid,areaname from {$table}area where areaid='$areaid'")

$here[] = array('name'=>$here_area['areaname'],'id'=>$here_area['areaid'])

测试通过，因为我正在使用.....................................

config.php代码：

<?php

$db_host = "localhost"

$db_name = "test"

$db_user = "root"

$db_pass = ""

$table = "mini_"

$charset = "gb2312"

$dbcharset = "gbk"

?>

mysql.class.php代码：

<?php

class mysql

{

var $link= NULL

//自动执行__construct php5类构建方法，如果PHP4和PHP5同时使用会自动使用PHP5的方法

function __construct($dbhost, $dbuser, $dbpw, $dbname = '', $pconnect = 0, $quiet = 0)

{

//自动执行时调用mysql函数

$this->mysql($dbhost, $dbuser, $dbpw, $dbname, $pconnect, $quiet)

}

//php4类构建方法，如果没有 __construct 就自动执行此功能

function mysql($dbhost, $dbuser, $dbpw, $dbname = '', $pconnect = 0, $quiet = 0)

{

if ($quiet)

{

$this->connect($dbhost, $dbuser, $dbpw, $dbname, $pconnect, $quiet)

}

else

{

$this->settings = array(

'dbhost' =>$dbhost,

'dbuser' =>$dbuser,

'dbpw' =>$dbpw,

'dbname' =>$dbname,

'charset' =>$charset,

'pconnect' =>$pconnect

)

}

}

function connect($dbhost, $dbuser, $dbpw, $dbname = '', $pconnect = 0, $quiet = 0)

{

global $dbcharset

if ($pconnect)

{

if (!($this->link = @mysql_pconnect($dbhost, $dbuser, $dbpw)))

{

if (!$quiet)

{

$this->ErrorMsg("Can't pConnect MySQL Server($dbhost)!")

}

return false

}

}

else

{

if (PHP_VERSION >= '4.2')

{

$this->link = @mysql_connect($dbhost, $dbuser, $dbpw, true)

}

else

{

$this->link = @mysql_connect($dbhost, $dbuser, $dbpw)

mt_srand((double)microtime() * 1000000)

}

if (!$this->link)

{

if (!$quiet)

{

$this->ErrorMsg("Can't Connect MySQL Server($dbhost)!")

}

return false

}

}

$this->dbhash = md5($this->root_path . $dbhost . $dbuser . $dbpw . $dbname)

$this->version = mysql_get_server_info($this->link)

if ($this->version >'4.1')

{

if ($dbcharset != 'latin1')

{

mysql_query("SET character_set_connection=$dbcharset, character_set_results=$dbcharset, character_set_client=binary", $this->link)

}

if ($this->version >'5.0.1')

{

mysql_query("SET sql_mode=''", $this->link)

}

}

if ($dbname)

{

if (mysql_select_db($dbname, $this->link) === false )

{

if (!$quiet)

{

$this->ErrorMsg("Can't select MySQL database($dbname)!")

}

return false

}

else

{

return true

}

}

else

{

return true

}

}

function query($sql, $type = '')

{

if ($this->link === NULL)

{

$this->connect($this->settings['dbhost'], $this->settings['dbuser'], $this->settings['dbpw'], $this->settings['dbname'], $this->settings['charset'], $this->settings['pconnect'])

$this->settings = array()

}

if ($this->queryCount++ <= 99)

{

$this->queryLog[] = $sql

}

if ($this->queryTime == '')

{

if (PHP_VERSION >= '5.0.0')

{

$this->queryTime = microtime(true)

}

else

{

$this->queryTime = microtime()

}

}

if (!($query = mysql_query($sql, $this->link)) &&$type != 'SILENT')

{

$this->error_message[]['message'] = 'MySQL Query Error'

$this->error_message[]['sql'] = $sql

$this->error_message[]['error'] = mysql_error($this->link)

$this->error_message[]['errno'] = mysql_errno($this->link)

$this->ErrorMsg()

return false

}

return $query

}

function affected_rows()

{

return mysql_affected_rows($this->link)

}

function num_fields($query)

{

return mysql_num_fields($query)

}

function error()

{

return mysql_error($this->link)

}

function errno()

{

return mysql_errno($this->link)

}

function num_rows($query)

{

return mysql_num_rows($query)

}

function insert_id()

{

return mysql_insert_id($this->link)

}

function fetchRow($query)

{

return mysql_fetch_assoc($query)

}

function fetcharray($query)

{

return mysql_fetch_array($query)

}

function version()

{

return $this->version

}

function close()

{

return mysql_close($this->link)

}

function ErrorMsg($message = '', $sql = '')

{

if ($message)

{

echo "$message\n\n"

}

else

{

echo "<b>MySQL server error report:"

print_r($this->error_message)

}

exit

}

function getCol($sql)

{

$res = $this->query($sql)

if ($res !== false)

{

$arr = array()

while ($row = mysql_fetch_row($res))

{

$arr[] = $row[0]

}

return $arr

}

else

{

return false

}

}

function getOne($sql, $limited = false)

{

if ($limited == true)

{

$sql = trim($sql . ' LIMIT 1')

}

$res = $this->query($sql)

if ($res !== false)

{

$row = mysql_fetch_row($res)

if ($row !== false)

{

return $row[0]

}

else

{

return ''

}

}

else

{

return false

}

}

function getAll($sql)

{

$res = $this->query($sql)

if ($res !== false)

{

$arr = array()

while ($row = mysql_fetch_assoc($res))

{

$arr[] = $row

}

return $arr

}

else

{

return false

}

}

//使用： getRow($sql,true) 如果有true那值是 limit 1,读取一条信息

function getRow($sql, $limited = false)

{

if ($limited == true)

{

$sql = trim($sql . ' LIMIT 1')

}

$res = $this->query($sql)

if ($res !== false)

{

return mysql_fetch_assoc($res)

}

else

{

return false

}

}

}

?>

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