有3层不同的过滤器：books，authors和stores（select列表），我可以使用他们一起一次或者只有一两个人，所以我使用UNION让所有查询一起绑定多个阵列
require('database.php');
if(isset($_POST['books'])){
$books_ids = $_POST["books"];
}
if(isset($_POST['authors'])){
$authors_ids = $_POST["authors"];
}
if(isset($_POST['stores'])){
$stores_ids = $_POST["stores"];
}
$query = "";
if(!empty($books_ids))
{
$books_ids_in = implode(',', array_fill(0, count($books_ids), '?'));
$query .= "SELECT
b.id,
b.`name`,
b.`year`,
GROUP_CONCAT(DISTINCT a.`name`) AS author_names,
GROUP_CONCAT(DISTINCT s.`name`) AS store_names,
'book' as param
FROM
books AS b
LEFT JOIN books_authors AS b_a ON b.id = b_a.book_id
LEFT JOIN authors AS a ON a.id = b_a.author_id
LEFT JOIN books_stores AS b_s ON b.id = b_s.book_id
LEFT JOIN stores AS s ON s.id = b_s.store_id
WHERE
b.id IN (". $books_ids_in .")
GROUP BY b.id
ORDER BY b.id";
}
if(!empty($authors_ids))
{
$authors_ids_in = implode(',', array_fill(0, count($authors_ids), '?'));
if (!empty($query)) {
$query .= " UNION ";
}
$query .= "SELECT
b.id,
b.`name`,
b.`year`,
GROUP_CONCAT(DISTINCT a.`name`) AS author_names,
GROUP_CONCAT(DISTINCT s.`name`) AS store_names,
'author' as param
FROM
books AS b
LEFT JOIN books_authors AS b_a ON b.id = b_a.book_id
LEFT JOIN authors AS a ON a.id = b_a.author_id
LEFT JOIN books_stores AS b_s ON b.id = b_s.book_id
LEFT JOIN stores AS s ON s.id = b_s.store_id
WHERE
b.id IN (
SELECT DISTINCT book_id FROM books_authors WHERE author_id IN (". $authors_ids_in .")
)
GROUP BY b.id
ORDER BY b.id";
}
if(!empty($stores_ids))
{
$stores_ids_in = implode(',', array_fill(0, count($stores_ids), '?'));
if (!empty($query)) {
$query .= " UNION ";
}
$query .= "SELECT
b.id,
b.`name`,
b.`year`,
GROUP_CONCAT(DISTINCT a.`name`) AS author_names,
GROUP_CONCAT(DISTINCT s.`name`) AS store_names,
'store' as param
FROM
books AS b
LEFT JOIN books_authors AS b_a ON b.id = b_a.book_id
LEFT JOIN authors AS a ON a.id = b_a.author_id
LEFT JOIN books_stores AS b_s ON b.id = b_s.book_id
LEFT JOIN stores AS s ON s.id = b_s.store_id
WHERE
b.id IN (
SELECT DISTINCT book_id FROM books_stores WHERE store_id IN (". $stores_ids_in .")
)
GROUP BY b.id
ORDER BY b.id";
}
if(!empty($query)) {
$stmt = $conn->prepare($query);
if(!empty($books_ids))
{
foreach ($books_ids as $k => $id) {
$stmt->bindValue(($k+1), $id);
}
}
if(!empty($authors_ids))
{
foreach ($authors_ids as $k => $id) {
$stmt->bindValue(($k+1), $id);
}
}
if(!empty($stores_ids))
{
foreach ($stores_ids as $k => $id) {
$stmt->bindValue(($k+1), $id);
}
}
$stmt->execute();
$results = $stmt->fetchAll();
echo json_encode($results);
}
$conn = null;
代码工作得很好，当我只用一个过滤器，但是当我尝试使用2个或更多，我得到错误
Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens' in C:\xampp\htdocs\bookstore\filter.php:123 Stack trace: #0 C:\xampp\htdocs\bookstore\filter.php(123): PDOStatement->execute() #1 {main} thrown in C:\xampp\htdocs\bookstore\filter.php on line 123
我想，什么是错的与bindValue使用，但我不知道如何解决这个问题？
UPD var_dump($query)（3本书和2名作者选择）
string(1097) "SELECT b.id, b.名, b.年, GROUP_CONCAT(DISTINCT a.名) AS author_names, GROUP_CONCAT(DISTINCT s.名) AS store_names, 'book' as param FROM books AS b LEFT JOIN books_authors AS b_a ON b.id = b_a.book_id LEFT JOIN authors AS a ON a.id = b_a.author_id LEFT JOIN books_stores AS b_s ON b.id = b_s.book_id LEFT JOIN stores AS s ON s.id = b_s.store_id WHERE b.id IN (?,?,?) GROUP BY b.id ORDER BY b.id UNION SELECT b.id, b.名, b.年, GROUP_CONCAT(DISTINCT a.名) AS author_names, GROUP_CONCAT(DISTINCT s.名) AS store_names, 'author' as param FROM books AS b LEFT JOIN books_authors AS b_a ON b.id = b_a.book_id LEFT JOIN authors AS a ON a.id = b_a.author_id LEFT JOIN books_stores AS b_s ON b.id = b_s.book_id LEFT JOIN stores AS s ON s.id = b_s.store_id WHERE b.id IN (SELECT DISTINCT book_id FROM books_authors WHERE author_id IN (?,?)) GROUP BY b.id ORDER BY b.id" 01201
该错误意味着你有更少/更多的绑定值比预期的查询。我会回显出每个bindValue循环的计数来找到罪魁祸首。 –
不，参数的数量与查询中的数量相同，我已经检查过。我选择了3本书和2位作者，并在我的查询WHERE b.id IN（？，？，？）和WHERE author_id IN（？，？））中查询了var_dump（$ query）;' – Heidel
var_dump并显示结果请 –