php与mysql是黄金组合,现在我们来讲一下关于php查询mysql数据库记录实现,主要会用到函数mysql_connect mysql_query mysql_select_db mysql_fetch_array四个php函数,下面看实现。$phps教程ql_user = "root";
$phpsql_password = "root";
$phpsql_loc = "";
$phpsql_db = "";
function phpsql_connect($location, $username, $password){
global $phpsql_loc, $phpsql_user, $phpsql_password;
if($phpsql_user != $username || $phpsql_password != $password)
phpsql_error("cannot access to phpsql!(wrong username/wrong password)");
define(phpsql_loc, $location);
$phpsql_loc = $location;
}
function phpsql_select_db($db){
global $phpsql_db;
define(phpsql_db, $db);
$phpsql_db = $db;
}
function phpsql_list_table(){
global $phpsql_loc, $phpsql_db;
$i = 0;
if(!($handle = @opendir($phpsql_loc."/".$phpsql_db)))
return 0;
while(($file = readdir($handle)) !== false){
if($file != "." && $file != "..")
{
$table[$i ++] = $file;
}
}
return $table;
}
$hostname="localhost"; //定义连接到的mysql服务器名
$username="root"; //定义用于连接的用户名
$password=""; //定义用于连接的密码
$link=mysql_connect($hostname,$username,$password); //打开msql连接
mysql_query('set names gb2312;'); //转换编码以支持中文
mysql_select_db("test"); //选择操作库为test
$query="select * from friends"; //定义sql
$result=mysql_query($query); //发送sql查询
while($rows=mysql_fetch_array($result))
{
echo "id为:".$rows[id];
echo "<br>www.111cn.netn";
echo "name为:".$rows[name];
echo "<br>n";
echo "sex为:".$rows[sex];
echo "<br>n";
echo "birthday为:".$rows[birthday];
echo "<br>n";
echo "address为:".$rows[address];
echo "<p>n";
}
//释放结果集
mysql_free_result($result);
//条件查询
$query="select * from friends where id=1"; //定义sql
$result= mysql_query($query); //发送sql查询
echo mysql_result($result,0,"name"); //输出name结果
echo "<br>";
echo mysql_result($result,0,"birthday"); //输出birthday结果
echo "<br>";
echo mysql_result($result,0,"sex"); //输出sex结果
echo "<br>";
echo mysql_result($result,0,"address"); //输出address结果
//相关操作
$conn=mysql_connect('localhost','root',''); //打开连接
$fields=mysql_list_fields("test","friends",$conn); //列出test库friends表的信息
$cols=mysql_num_fields($fields); //获取结果数
for($i=0;$i<$cols;$i++) //循环
{
echo mysql_field_name($fields,$i)."n"; //输出字段名
echo "<p>";
}
/*
总结
在php中查询数据库记录是相当简单且常用的,只要你记录上面几个函数就可以实现数据查询了。
*/
这里提供的数据库连接类程序,后面还提供了一个sql安全检测函数与sql语句完整性检测函数。*/
class db_mysql {
var $connid;
var $querynum = 0;
var $expires;
var $cursor = 0;
var $cache_id = '';
var $cache_file = '';
var $cache_expires = '';
var $halt = 0;
var $result = array();function connect($dbhost, $dbuser, $dbpw, $dbname, $pconnect = 0) {
global $cfg;
$this->expires = $cfg['db_expires'];
$func = $pconnect == 1 ? 'mysql_pconnect' : 'mysql_connect';
if(!$this->connid = $func($dbhost, $dbuser, $dbpw)) {
$this->halt('can not connect to mysql server');
}
if($this->version() > '4.1' && $cfg['db_charset']) {
mysql_query("set names '".$cfg['db_charset']."'" , $this->connid);
}
if($this->version() > '5.0') {
mysql_query("set sql_mode=''" , $this->connid);
}
if($dbname) {
if(!mysql_select_db($dbname , $this->connid)) {
$this->halt('cannot use database '.$dbname);
}
}
return $this->connid;
}function select_db($dbname) {
return mysql_select_db($dbname , $this->connid);
}function query($sql , $type = '', $expires = 0, $save_id = false) {
$sql=checksql($sql);
if($type == 'cache' && stristr($sql, 'select')) {
$this->cursor = 0;
$this->cache_id = md5($sql);
$this->result = array();
$this->cache_expires = $expires ? $expires + mt_rand(-9, 9) : $this->expires;
return $this->_query($sql);
}
if(!$save_id) $this->cache_id = 0;
$func = $type == 'unbuffered' ? 'mysql_unbuffered_query' : 'mysql_query';
if(!($query = $func($sql , $this->connid)) && $this->halt) {
$this->halt('mysql query error', $sql);
}
$this->querynum++;
return $query;
}function get_one($sql, $type = '', $expires = 0) {
$query = $this->query($sql, $type, $expires);
$r = $this->fetch_array($query);
$this->free_result($query);
return $r ;
}
function counter($table, $condition = '', $type = '', $expires = 0) {
global $cfg;
$table = strpos($table, $cfg['tb_pre']) === false ? $cfg['tb_pre'].$table : $table;
$sql = "select count(*) as num from {$table}";
if($condition) $sql .= " where $condition";
$r = $this->get_one($sql, $type, $expires);
return $r ? $r['num'] : 0;
}function fetch_array($query, $result_type = mysql_assoc) {
return $this->cache_id ? $this->_fetch_array($query) : @mysql_fetch_array($query, $result_type);
}function affected_rows() {
return mysql_affected_rows($this->connid);
}function num_rows($query) {
return mysql_num_rows($query);
}function num_fields($query) {
return mysql_num_fields($query);
}
function escape_string($str){
return mysql_escape_string($str);
}
function result($query, $row) {
return @mysql_result($query, $row);
}function free_result($query) {
return @mysql_free_result($query);
}function insert_id() {
return mysql_insert_id($this->connid);
}function fetch_row($query) {
return mysql_fetch_row($query);
}function version() {
return mysql_get_server_info($this->connid);
}function close() {
return mysql_close($this->connid);
}function error() {
return @mysql_error($this->connid);
}function errno() {
return intval(@mysql_errno($this->connid)) ;
}function halt($message = '', $sql = '') {
global $cfg;
if($message) {
if($cfg['errlog']) {
$log = "query:$sql|errno:".$this->errno()."|error:".$this->error()."|errmsg:$message";
log_write($log, 'sql');
}
}
showmsg("mysqlerror:$message",'-1');
exit();
}function _query($sql) {
global $fr_time;
$this->cache_file = cache_root.'/sql/'.substr($this->cache_id, 0, 2).'/'.$this->cache_id.'.php教程';
if(!is_file($this->cache_file) || ($fr_time - @filemtime($this->cache_file) > $this->cache_expires)) {
$tmp = array();
$result = $this->query($sql, '', '', true);
while($r = mysql_fetch_array($result, mysql_assoc)) {
$tmp[] = $r;
}
$this->result = $tmp;
$this->free_result($result);
file_put($this->cache_file, "<?php /*".( $fr_time+$this->cache_expires)."*/ return ".var_export($this->result, true).";n?>");
} else {
$this->result = include $this->cache_file;
}
return $this->result;
}function _fetch_array($query = array()) {
if($query) $this->result = $query;
if(isset($this->result[$this->cursor])) {
return $this->result[$this->cursor++];
} else {
$this->cursor = $this->cache_id = 0;
return array();
}
}
}function checksql($dbstr,$querytype='select'){
$clean = '';
$old_pos = 0;
$pos = -1;
//普通语句,直接过滤特殊语法
if($querytype=='select'){
$nastr = "/[^0-9a-z@._-]{1,}(union|sleep|benchmark|load_file|outfile)[^0-9a-z@.-]{1,}/i";
if(preg_match($nastr,$dbstr)){
log_write($dbstr,'sql');
showmsg('safeerror:10001', '网页特效:;');
exit();
}
}
//完整的sql检查
while (true){
$pos = strpos($dbstr, ''', $pos + 1);
if ($pos === false){
break;
}
$clean .= substr($dbstr, $old_pos, $pos - $old_pos);
while (true){
$pos1 = strpos($dbstr, ''', $pos + 1);
$pos2 = strpos($dbstr, '', $pos + 1);
if ($pos1 === false){
break;
}
elseif ($pos2 == false || $pos2 > $pos1){
$pos = $pos1;
break;
}
$pos = $pos2 + 1;
}
$clean .= '$s$';
$old_pos = $pos + 1;
}
$clean .= substr($dbstr, $old_pos);
$clean = trim(strtolower(preg_replace(array('~s+~s' ), array(' '), $clean)));
if (strpos($clean, 'union') !== false && preg_match('~(^|[^a-z])union($|[^[a-z])~s', $clean) != 0){
$fail = true;
}
elseif (strpos($clean, '/*') > 2 || strpos($clean, '--') !== false || strpos($clean, '#') !== false){
$fail = true;
}
elseif (strpos($clean, 'sleep') !== false && preg_match('~(^|[^a-z])sleep($|[^[a-z])~s', $clean) != 0){
$fail = true;
}
elseif (strpos($clean, 'benchmark') !== false && preg_match('~(^|[^a-z])benchmark($|[^[a-z])~s', $clean) != 0){
$fail = true;
}
elseif (strpos($clean, 'load_file') !== false && preg_match('~(^|[^a-z])load_file($|[^[a-z])~s', $clean) != 0){
$fail = true;
}
elseif (strpos($clean, 'into outfile') !== false && preg_match('~(^|[^a-z])intos+outfile($|[^[a-z])~s', $clean) != 0){
$fail = true;
}
elseif (preg_match('~([^)]*?select~s', $clean) != 0){
$fail = true;
}
if (!empty($fail)){
log_write($dbstr,'sql');
showmsg('safeerror:10002', 'javascript:;');exit;
}
else
{
return $dbstr;
}
}
下面只告诉你如何实现图片如何保存到数据库教程,不推荐此种方法。
*/
mysql_connect('localhost','root','root');
mysql_select_db('ac');
$picdir ="/a/ag.gif";
$image = addslashes(file_get_contents($picdir));
$sql ="insert into tbl_name (field) values ('" . $image . "')";
mysql_query($sql);
/*
--
-- 表的结构 `test`
--
create table if not exists `test` (
`id` int(8) not null auto_increment,
`title` char(150) default null,
`content` longblob,
`addnewcolumn` varchar(20) not null,
primary key (`id`)
) engine=myisam default charset=utf8 auto_increment=1 ;
<html>
<head>
<title></title>
</head>
<body>
<?php
$mysql_server_name='localhost';
$mysql_username='root';
$mysql_password='000000';
$mysql_database='lib';
$conn=mysql_connect($mysql_server_name,$mysql_username,$mysql_password,$mysql_database);
$sql="select name,age from mytb";
print($conn);
$rs=mysql_db_query("lib","select * from mytb",$conn);
print("
<br>");
while($row = mysql_fetch_object($rs)){
print ($row->name.":".$row->age."<br>");
}
mysql_close($conn);
?>
显示如下:
resource id #1
dd:54
ddd:8
??:15
???:25
??:32
mysql编码:utf8,gbk都试过了。mysql font 和命令行显示都正确。
问题补充:
乱码:
???:15
???:25
??:32
这几行,数据库教程里的值是汉字.显示出来的是问号.
解决办法:
在$rs=mysql_db_query("lib","select * from mytb",$conn);
前面加上
mysql_query("set names gb2312");或者mysql_query("set names gbk");
下面看一下关于解决乱码的方法
.gb2312,gbk,utf8等支持多字节编码的字符集都可以储存汉字,gb2312中的汉字数量远少于gbk,而gb2312,gbk等都可在utf8下编码。
二.用命令show variables like 'character_set_%';查看当前字符集设定:
mysql> show variables like 'character_set_%';
+--------------------------+--------+
| variable_name | value |
+--------------------------+--------+
| character_set_client | gb2312 |
| character_set_connection | gb2312 |
| character_set_database | gb2312 |
| character_set_filesystem | binary |
| character_set_results | gb2312 |
| character_set_server | latin1 |
| character_set_system | utf8 |
+--------------------------+--------+
7 rows in set (0.02 sec)
(这里设置的字符是gb2312)
显示中文乱码主要有两个设置:character_set_connection 和character_set_results ,
如果你的这两个设置不支持中文编码,就会出现乱码,只要:set character_set_results =gbk;就设置中文编码了。
三.set names charset_name;可以一次性设置客户端的所有字符集。