在 PHP 中,您可以使用多种方法与 Linux 上的数据库进行交互。以下是一些常见的数据库及其对应的 PHP 扩展和示例:
要使用 PHP 与 MySQL 数据库交互,您需要安装并启用 mysqli 或 PDO_MySQL 扩展。
使用 mysqli:
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);
// 检查连接
if ($conn->connect_error) {
die("连接失败: " . $conn->connect_error);
}
// 查询数据
$sql = "SELECT id, name FROM myTable";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// 输出每行数据
while($row = $result->fetch_assoc()) {
echo "id: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
}
} else {
echo "0 结果";
}
$conn->close();
使用 PDO_MySQL:
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
// 设置 PDO 错误模式为异常
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
// 查询数据
$stmt = $conn->query("SELECT id, name FROM myTable");
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
echo "id: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
}
} catch(PDOException $e) {
echo "连接失败: " . $e->getMessage();
}
$conn = null;
要使用 PHP 与 PostgreSQL 数据库交互,您需要安装并启用 pgsql 或 PDO_PGSQL 扩展。
使用 pgsql:
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// 创建连接
$conn = pg_connect("host=$servername dbname=$dbname user=$username password=$password");
// 检查连接
if (!$conn) {
echo "连接失败";
exit;
}
// 查询数据
$query = "SELECT id, name FROM myTable";
$result = pg_query($conn, $query);
if ($result) {
while ($row = pg_fetch_assoc($result)) {
echo "id: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
}
} else {
echo "查询失败";
}
pg_close($conn);
使用 PDO_PGSQL:
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
try {
$conn = new PDO("pgsql:host=$servername;dbname=$dbname", $username, $password);
// 设置 PDO 错误模式为异常
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
// 查询数据
$stmt = $conn->query("SELECT id, name FROM myTable");
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
echo "id: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
}
} catch(PDOException $e) {
echo "连接失败: " . $e->getMessage();
}
$conn = null;
请根据您的需求选择合适的数据库扩展,并确保已正确安装和配置。