PHP使用PDO操作MySQL

gistfile1.php

function getConnection() {
  $dbhost="127.0.0.1";
	$dbuser="root";
	$dbpass="root";
	$dbname="cellar";
	$dbh = new PDO("mysql:host=$dbhost;dbname=$dbname", $dbuser, $dbpass, array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES 'utf8';"));	
	$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
	return $dbh;
}

function deleteWine($id) {
  $sql = "DELETE FROM wine WHERE id=:id";
	try {
		$db = getConnection();
		$stmt = $db->prepare($sql);  
		$stmt->bindParam("id", $id);
		$stmt->execute();
		$db = null;
	} catch(PDOException $e) {
		echo '{"error":{"text":'. $e->getMessage() .'}}'; 
	}
}

function getWine($id) {
  $sql = "SELECT * FROM wine WHERE id=:id";
	try {
		$db = getConnection();
		$stmt = $db->prepare($sql);  
		$stmt->bindParam("id", $id);
		$stmt->execute();
		$wine = $stmt->fetchObject();  
		$db = null;
		echo json_encode($wine); 
	} catch(PDOException $e) {
		echo '{"error":{"text":'. $e->getMessage() .'}}'; 
	}
}

function getWines() {
  $sql = "select * FROM wine ORDER BY name";
	try {
		$db = getConnection();
		$stmt = $db->query($sql);  
		$wines = $stmt->fetchAll(PDO::FETCH_OBJ);
		$db = null;
		echo '{"wine": ' . json_encode($wines) . '}';
	} catch(PDOException $e) {
		echo '{"error":{"text":'. $e->getMessage() .'}}'; 
	}
}