使用 PHP 创建数据库118

简介在 PHP 中，使用 MySQLi 扩展是创建和管理数据库的推荐方式。MySQLi 提供了与 MySQL 数据库服务器交互的高级接口，使其成为一个强大且灵活的工具。

先决条件* 安装 PHP 和 MySQLi 扩展
* 配置 MySQL 服务器并创建数据库用户

步骤1. 建立连接
```php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database_name";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
die("连接失败: " . $conn->connect_error);
}
```
2. 创建数据库
```php
$sql = "CREATE DATABASE IF NOT EXISTS myDB";
if ($conn->query($sql) === TRUE) {
echo "数据库创建成功";
} else {
echo "创建数据库失败: " . $conn->error;
}
```
3. 选择数据库
```php
$conn->select_db("myDB");
```
4. 创建表
```php
$sql = "CREATE TABLE users (
id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(30) NOT NULL,
email VARCHAR(50) NOT NULL
)";
if ($conn->query($sql) === TRUE) {
echo "表创建成功";
} else {
echo "创建表失败: " . $conn->error;
}
```
5. 插入数据
```php
$sql = "INSERT INTO users (name, email) VALUES ('John Doe', '@')";
if ($conn->query($sql) === TRUE) {
echo "数据插入成功";
} else {
echo "数据插入失败: " . $conn->error;
}
```
6. 查询数据
```php
$sql = "SELECT * FROM users";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while ($row = $result->fetch_assoc()) {
echo "id: " . $row["id"] . " - Name: " . $row["name"] . " - Email: " . $row["email"] . "
";
}
} else {
echo "0 结果";
}
```
7. 关闭连接
```php
$conn->close();
```