How to access mysql database in php?

Methods to access the mysql database in php: 1. Use mysqli_connect() to connect to the mysql database for access; 2. Use mysqli() to connect to the mysql database for access; 3. Use PDO to connect to the database for access .

Recommended: "PHP Video Tutorial"

#How to access the mysql database in php ：

Method 1: Use mysqli_connect() to connect to the mysql database for access

mysqli_connect() function opens a new connection to the MySQL server connect.

Syntax

mysqli_connect(host,username,password,dbname,port,socket);

Parameters:

• host Optional. Specify the hostname or IP address.

• username Optional. Specifies the MySQL username.

• password Optional. Specifies the MySQL password.

• dbname Optional. Specifies the database to use by default.

• port Optional. Specifies the port number to attempt to connect to the MySQL server.

• socket Optional. Specifies the socket or named pipe to use.

Example:

<?php
$con=mysqli_connect("localhost","wrong_user","my_password","my_db");
// 检查连接
if (!$con)
{
    die("连接错误: " . mysqli_connect_error());
}
?>

Method 2: Use mysqli() to connect to the mysql database

MYSQLi function is in PHP5.0.0 A new driver method was introduced in this version, and its function is to operate the MYSQL database.

<?php
$host=&#39;127.0.0.1&#39;;
$user=&#39;root&#39;;
$password=&#39;root&#39;;
$dbName=&#39;php&#39;;
$link=new mysqli（$host,$user,$password,$dbName）；
if （$link->connect_error）{
die（"连接失败：".$link->connect_error）；
}
$sql="select * from admins";
$res=$link->query（$sql）；
$data=$res->fetch_all（）；
var_dump（$data）；

Method 3: Use PDO to connect to the database

The PHP Data Object (PDO) extension defines a lightweight consistent interface for PHP to access the database.

PDO provides a data access abstraction layer, which means that no matter which database is used, the same functions (methods) can be used to query and obtain data.

Code examples are as follows:

<?php
$host=&#39;127.0.0.1&#39;;
$user=&#39;root&#39;;
$password=&#39;root&#39;;
$dbName=&#39;php&#39;;
$pdo=new PDO（"mysql:host=$host;dbname=$dbName",$user,$password）；
$sql="select * from admins";
$data=$pdo->query（$sql）->fetch（）；
var_dump（$data）；

Related recommendations: php training

The above is the detailed content of How to access mysql database in php?. For more information, please follow other related articles on the PHP Chinese website!