


'The Quickest to Understand PHP Programming' Lecture 6: Mysql Database Operation_PHP Tutorial
The answer is to make it a class-the database class is produced. Through the secondary encapsulation of functions, very good reuse is achieved. Include it when you want to use it.
Before talking about the PHP database, let me first introduce the key points of Mysql: You can use phpmyadmin to learn database operations.
In phpmyadmin, if you see the encoding item, just select Chinese utf-8.
Mysql database types are mainly: char (fixed space string, as many Chinese characters as it can be), varchar (variable space string, as many Chinese characters as it can be initialized), int (as many integers as it can be initialized) bits), float (floating point number), timestamp (date, optionally created automatically when created, the output is already formatted date), text (text), bool (Boolean)
Write sql SUM() can count values when making statements; order by 'id' DESC LIMIT 10,10, etc. should be used flexibly.
Just learn to add, delete, modify and check sql statements in phpmyadmin.
Example 20 Mysql class
class opmysql{
private $host = 'localhost'; //Server address
private $name = 'root'; //Login account
private $pwd = ''; //Login password
private $dBase = 'a0606123620'; //Database name
private $conn = ''; //Database link resource
private $result = ''; //Result set
private $msg = ''; //Return results
private $fields; //Return fields
private $fieldsNum = 0; //Return number of fields
private $rowsNum = 0; //Return the number of results
private $rowsRst = ''; //Return the field array of a single record
private $filesArray = array(); //Return the field array
private $rowsArray = array( ); //Return the result array
private $idusername=array();
private $idsubtitle=array();
//Initialize class
function __construct($host='',$name ='',$pwd='',$dBase=''){
if($host != '')
$this->host = $host;
if($name ! = '')
$this->name = $name;
if($pwd != '')
$this->pwd = $pwd;
if($dBase ! = '')
$this->dBase = $dBase;
$this->init_conn();
}
//Link to database
function init_conn(){
$this->conn=@mysql_connect($this->host,$this->name,$this->pwd);
@mysql_select_db($this->dBase,$this-> ;conn);
mysql_query("set names utf8");
}
//Query results
function mysql_query_rst($sql){
if($this->conn == ''){
$this->init_conn();
}
$this->result = @mysql_query($sql,$this->conn);
}
//Get the number of query result fields
function getFieldsNum($sql){
$this->mysql_query_rst($sql);
$this->fieldsNum = @mysql_num_fields($this ->result);
}
//Get the number of query result rows
function getRowsNum($sql){
$this->mysql_query_rst($sql);
if(mysql_errno () == 0){
return @mysql_num_rows($this->result);
}else{
return '';
}
}
//Get the record The array has an index (single record)
function getRowsRst($sql){
$this->mysql_query_rst($sql);
if(mysql_error() == 0){
$this- >rowsRst = mysql_fetch_array($this->result,MYSQL_ASSOC);
return $this->rowsRst;
}else{
return '';
}
}
//Get all records array with index (multiple records)
function getRowsArray($sql){
$this->mysql_query_rst($sql);
if(mysql_errno() == 0) {
while($row = mysql_fetch_array($this->result,MYSQL_ASSOC)) {
$this->rowsArray[] = $row;
}
return $this-> rowsArray;
}else{
return '';
}
}
//Update, delete, add the number of records, return the number of affected rows
function uidRst($sql ){
if($this->conn == ''){
$this->init_conn();
}
@mysql_query($sql);
$this ->rowsNum = @mysql_affected_rows();
if(mysql_errno() == 0){
return $this->rowsNum;
}else{
return '';
}
}
//Get the corresponding field value, a numeric index, mysql_array_rows is the field index
function getFields($sql,$fields){
$this->mysql_query_rst($ sql);
if(mysql_errno() == 0){
if(mysql_num_rows($this->result) > 0){
$tmpfld = @mysql_fetch_row($this->result );
$this->fields = $tmpfld[$fields];
}
return $this->fields;
}else{
return '';
}
}
//Error message
function msg_error(){
if(mysql_errno() != 0) {
$this->msg = mysql_error ();
}
return $this->msg;
}
//Release the result set
function close_rst(){
mysql_free_result($this->result) ;
$this->msg = '';
$this->fieldsNum = 0;
$this->rowsNum = 0;
$this->filesArray = '' ;
$this->rowsArray = '';
$this->idsubtitle='';
$this->idusername='';
}
//Close Database
function close_conn(){
$this->close_rst();
mysql_close($this->conn);
$this->conn = '';
}
}
?>
Usage of Example 21 class, md5 encryption of passwords
$conne = new opmysql();
$conne-> getRowsArray($sql);
$conne-> close_conn ();
$password="123456一二三四五六";
echo md5($password."www.kuphp.com");//The output is 32-bit ciphertext, which is not decrypted Functional, can implement simple encryption functions.
?>

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