喜欢命令不在mysql中工作

Question

当我移除firstcomm Like %?%时，它可以正常工作。当我将其保留时，它无法返回结果（尽管脚本中没有实际错误）。是的，firstcomm是我数据库的一部分。那么为什么呢？我在做%?%错了吗？

$dbh = new PDO(...);
   $sql = 'SELECT ... FROM ... WHERE firstcomm LIKE %?% AND ...';
$params = array( $qu, ... );

$q = $dbh->prepare( $sql );
$q->execute( $params );
$doc = new DOMDocument();

更新：这也失败了......

$dbh = new PDO(...);
   $sql = 'SELECT ... FROM ... WHERE firstcomm LIKE ? AND ...';
$params = array( $qu, ... );

$q = $dbh->prepare( $sql );
$q->execute( $params );
$doc = new DOMDocument();

Answer 1

试试这个

$sql = "SELECT ... FROM ... WHERE firstcomm LIKE '%?%' AND ...";

Answer 2

$sql = 'SELECT ... FROM ... WHERE firstcomm LIKE ? AND ...';
$like = '%?%';
$stmt = $connection->prepare($sql);
$stmt->bind_param('s', $like);
$stmt->execute();