为什么PDO fetchAll（）返回两次相同的结果？

Question

我正在使用PDO在PHP中构建一个简单的搜索引擎。一切正常，但是fetchAll（PDO :: FETCH_ASSOC）两次返回相同的结果。

这是我的PHP代码： （已更新以显示 id 列...）

header('Content-Type: application/json');

$q = db()->prepare("SELECT id, title, description, type, mediaId FROM projects WHERE title LIKE ?");
$q->execute(array('%'.$search.'%'));
$d = $q->fetchAll(PDO::FETCH_ASSOC);

echo json_encode($d);

这是我从PDO获得的结果

[
{
"id" : "1",
"title": "PhonArt",
"description": "Games",
"type": "",
"mediaId": "linkA"
},
{
"id" : "1",
"title": "PhonArt",
"description": "Games",
"type": "",
"mediaId": "linkA"
},
{
"id" : "2",
"title": "BioState",
"description": "Biology",
"type": "",
"mediaId": "linkB"
},
{
"id" : "3",
"title": "SnaPhones Inc.",
"description": "A social network",
"type": "",
"mediaId": "linkC"
},
{
"id" : "2",
"title": "BioState",
"description": "Biology",
"type": "",
"mediaId": "linkB"
},
{
"id" : "3",
"title": "SnaPhones Inc.",
"description": "A social network",
"type": "",
"mediaId": "linkC"
}
]