Home Backend Development PHP Tutorial A PHP database connection class_PHP tutorial

A PHP database connection class_PHP tutorial

Jul 13, 2016 pm 05:05 PM
mysql php host Example supply Tutorial number database article kind connect

This article provides two database tutorial connection examples, mainly about data-related operations of the PHP tutorial and the MySQL tutorial. Friends in need can use it.

class mysql {
private $db_host; //Host address
private $db_user; //Username
private $db_pass; //Connection password
private $db_name; //name
private $db_charset; //Encoding
private $conn;
public $debug=false;//Debug switch, turned off by default
private $query_id; //Used to determine whether the sql statement is executed successfully
private $result; //result set
private $num_rows; //The number of rows in the result set, only valid for select
private $insert_id; //The id generated by the previous insert operation
// Constructor/Destructor
function __construct ($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);
}
// Connect/select database
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) {
$this->show_error('Database-Connection failed: Wrong username or password!');
}
if (!@mysql_select_db($this->db_name,$this->conn)) {
$this->show_error("Database-selection failed: Database $this->db_name is not available");
}
mysql_query("set names $this->db_charset");
return $this->conn;
}
// query method
public function query ($sql) {
if ($this->query_id) $this->free_result();
$this->query_id = @mysql_query($sql,$this->conn);
if (!$this->query_id) $this->show_error("sql statement "$sql" encountered an error during execution");
return $this->query_id;
}
// Display detailed error information
public function show_error ($msg) {
if($this->debug){
$errinfo = mysql_error();
echo "Error: $msg
Return: $errinfo

";
}else{
echo '

An error occurred!

';
}
}
// Get information about the success or failure of query execution
public function get_query_info($info){
if ($this->query_id) {
echo $info;
}
}
// Query all
public function findall ($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 $this->result;
}
}
// Get num_rows
public function num_rows () {
if ($this->query_id) {
$this->num_rows = mysql_num_rows($this->query_id);
return $this->num_rows;
}
}
// Get insert_id
public function insert_id () {
return $this->insert_id = mysql_insert_id();
}
//Show how many tables there are
public function show_tables () {
$this->query("show tables");
if ($this->query_id) {
echo "Database $this->db_name has ".$this->num_rows($this->query_id)." tables
";
$i = 1;
while ($row = $this->fetch_array($this->query_id)){
echo "$i -- $row[0]
";
$i++;
}
}
}
// Show how many databases there are in total
public function show_dbs(){
$this->query("show databases");
if ($this->query_id) {
echo "There are total databases ".$this->num_rows($this->query_id)."
";
$i = 1;
while ($this->row = $this->fetch_array($this->query_id)){
echo "$i -- ".$this->row[database]."
";
$i++;
}
}
}
//Delete database: return deletion result
public function drop_db ($db_name='') {
if ($db_name == '') {
$db_name = $this->db_name;//Delete the current database by default
$this->query("drop database $db_name");
}else {
$this->query("drop database $db_name");
}
if ($this->query_id) {
return "Database $db_name deleted successfully";
}else {
$this->show_error("Database $db_name deletion failed");
}
}
//Delete data table: return deletion result
public function drop_table ($table_name) {
$this->query("drop table $table_name");
if ($this->query_id) {
return "Data table $table_name deleted successfully";
}else {
$this->show_error("Deletion of data table $table_name failed");
}
}
//Create database
public function create_db ($db_name) {
$this->query("create database $db_name");
if($this->query_id){
return "Database $db_name created successfully";
}else {
$this->show_error("Database $db_name creation failed");
}
}
// Get database version
public function get_info(){
echo mysql_get_server_info();
}
// Release memory
public function free_result () {
if ( @mysql_free_result($this->query_id) )
unset ($this->result);
$this->query_id = 0;
}
} // end class
?>

The following provides an automatic selection database remote or local connection code

// Contains mysql operation class
include_once 'mysql.class.php';
// Local mysql data
$mysql_local_data = array('db_host'=>'localhost',
'db_user'=>'root',
'db_pass'=>'root',
'db_name'=>'test');
//Remote mysql data
$mysql_remote_data = array('db_host'=>'61.183.41.178',
'db_user'=>'xxx',
'db_pass'=>'xxx',
'db_name'=>'xxx');
// Public data
$tb_prefix = 'php95_';
$db_charset = 'utf-8';
//If the local connection is successful, instantiate the local mysql class, otherwise connect to the remote database and instantiate the mysql class
if (@mysql_connect($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(); //Test: display all table names under the current database
?>

Suppose we want to operate the database of the virtual host in the test.php file, we must first debug locally, then we must connect to two different databases, local and remote. Question: How to make test.php automatically recognize the current connection? Local or remote database?

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/630771.htmlTechArticleThis article provides two database tutorial connection examples, mainly about data-related operations of php tutorial mysql tutorial, if necessary Friends can use it to take a look. ?php class mysql { private $db_h...
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
WWE 2K25: How To Unlock Everything In MyRise
1 months ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

The Future of PHP: Adaptations and Innovations The Future of PHP: Adaptations and Innovations Apr 11, 2025 am 12:01 AM

The future of PHP will be achieved by adapting to new technology trends and introducing innovative features: 1) Adapting to cloud computing, containerization and microservice architectures, supporting Docker and Kubernetes; 2) introducing JIT compilers and enumeration types to improve performance and data processing efficiency; 3) Continuously optimize performance and promote best practices.

PHP vs. Python: Understanding the Differences PHP vs. Python: Understanding the Differences Apr 11, 2025 am 12:15 AM

PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.

MySQL: Simple Concepts for Easy Learning MySQL: Simple Concepts for Easy Learning Apr 10, 2025 am 09:29 AM

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

How to open phpmyadmin How to open phpmyadmin Apr 10, 2025 pm 10:51 PM

You can open phpMyAdmin through the following steps: 1. Log in to the website control panel; 2. Find and click the phpMyAdmin icon; 3. Enter MySQL credentials; 4. Click "Login".

MySQL and SQL: Essential Skills for Developers MySQL and SQL: Essential Skills for Developers Apr 10, 2025 am 09:30 AM

MySQL and SQL are essential skills for developers. 1.MySQL is an open source relational database management system, and SQL is the standard language used to manage and operate databases. 2.MySQL supports multiple storage engines through efficient data storage and retrieval functions, and SQL completes complex data operations through simple statements. 3. Examples of usage include basic queries and advanced queries, such as filtering and sorting by condition. 4. Common errors include syntax errors and performance issues, which can be optimized by checking SQL statements and using EXPLAIN commands. 5. Performance optimization techniques include using indexes, avoiding full table scanning, optimizing JOIN operations and improving code readability.

PHP: Is It Dying or Simply Adapting? PHP: Is It Dying or Simply Adapting? Apr 11, 2025 am 12:13 AM

PHP is not dying, but constantly adapting and evolving. 1) PHP has undergone multiple version iterations since 1994 to adapt to new technology trends. 2) It is currently widely used in e-commerce, content management systems and other fields. 3) PHP8 introduces JIT compiler and other functions to improve performance and modernization. 4) Use OPcache and follow PSR-12 standards to optimize performance and code quality.

How to use single threaded redis How to use single threaded redis Apr 10, 2025 pm 07:12 PM

Redis uses a single threaded architecture to provide high performance, simplicity, and consistency. It utilizes I/O multiplexing, event loops, non-blocking I/O, and shared memory to improve concurrency, but with limitations of concurrency limitations, single point of failure, and unsuitable for write-intensive workloads.

phpmyadmin connection mysql phpmyadmin connection mysql Apr 10, 2025 pm 10:57 PM

How to connect to MySQL using phpMyAdmin? The URL to access phpMyAdmin is usually http://localhost/phpmyadmin or http://[your server IP address]/phpmyadmin. Enter your MySQL username and password. Select the database you want to connect to. Click the "Connection" button to establish a connection.

See all articles