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author:php.cn  update time:2022-04-15 13:53:54

PHP MySQL creates database




The database has one or more tables.

You need CREATE permission to create or delete MySQL database.


Creating a MySQL database using MySQLi and PDO

The CREATE DATABASE statement is used to create a database in MySQL.

In the following example, a database named "myDB" is created:

Instance (MySQLi - Object-oriented)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
// 创建连接
$conn = 
new mysqli($servername, $username, $password);
// 检测连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}
// 创建数据库
$sql = "CREATE DATABASE myDB";
if ($conn->query($sql) === TRUE) {
    
echo "数据库创建成功";
} else {
    echo 
"Error creating database: " . $conn->error;
}
$conn->close();
?>

Example (MySQLi Procedural)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
// 创建连接
$conn = mysqli_connect($servername, 
$username, $password);
// 检测连接
if (!$conn) {
    die("连接失败: " . mysqli_connect_error());
}
// 创建数据库
$sql = "CREATE 
DATABASE myDB";
if (mysqli_query($conn, $sql)) {
    echo "数据库创建成功";
} else {
    echo "Error 
creating database: " . mysqli_error($conn);
}
mysqli_close($conn);
?>

Note: The following uses PDO instance to create database "myDBPDO":

Instance

Use PDO:

<?php
$servername
= "localhost";
$username = "username";
$password = " password";

try {
$conn = new PDO( "mysql:host=$servername;dbname=myDB", $username, $password);

// Set PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE , PDO::ERRMODE_EXCEPTION);
$sql = "CREATE DATABASE myDBPDO";

// Use exec() because no result is returned
$ conn->exec($sql);

echo
"Database created successfully<br>";
}
catch(
PDOException $e)
{
echo
$sql . "<br>" . $e-> ;getMessage();
}

$conn = null;
?>

## Tips: The biggest benefit of using PDO is to query in the database When there is a problem in the process, you can use the exception class to solving issues. If an exception occurs in the try{ } code block, the script will stop execution and jump to the first catch(){ } code block to execute the code. In the code block captured above we output the SQL statement and generate the error message.

Related video tutorial recommendations: "mysql tutorial"//m.sbmmt.com/course/list/51.html


Note##Note: When you create a new database, you must specify three parameters for the mysqli object ( servername, username and password).

Tip: If you use another port (default is 3306), add an empty string for the database parameter, such as: new mysqli("localhost", "username", "password", "", port)