传递DBI时出现perl错误->；执行IN子句中的值

我有一个查询，用于根据此处的文档计算位于某个点的某个半径内的对象：

它工作得很好，但是我只想搜索那些特定类型的对象，这会导致一个问题

代码如下所示：

my $sql = "SELECT *
 FROM (
 SELECT b.*, pr.postcode, pr.prize, pr.title, pr.collection, pr.redeemed, pr.delivery, pr.archived, bt.category,
        p.radius,
        p.distance_unit
                 * DEGREES(ACOS(COS(RADIANS(p.latpoint))
                 * COS(RADIANS(b.lat))
                 * COS(RADIANS(p.longpoint - b.lng))
                 + SIN(RADIANS(p.latpoint))
                 * SIN(RADIANS(b.lat)))) AS distance
  FROM bubbles AS b, bubble_prizes AS pr, bubble_types AS bt
  JOIN (   /* these are the query parameters */
        SELECT  ?  AS latpoint, ? AS longpoint,
                ? AS radius,      ? AS distance_unit
    ) AS p
  WHERE b.lat
     BETWEEN p.latpoint  - (p.radius / p.distance_unit)
         AND p.latpoint  + (p.radius / p.distance_unit)
    AND b.lng
     BETWEEN p.longpoint - (p.radius / (p.distance_unit * COS(RADIANS(p.latpoint))))
         AND p.longpoint + (p.radius / (p.distance_unit * COS(RADIANS(p.latpoint))))
    AND pr.bubble = b.id
    AND b.type IN ?
    AND b.type = bt.type
 ) AS d
 WHERE distance <= radius
 ORDER BY distance";    

其中“（type1，type2）”应传递给

b.type IN ?

（位于SQL语句的底部附近）

我已经尝试了所有我能想到的方法来摆脱这个字符串，这样它就可以工作了（包括很多明显疯狂但我绝望的方法）

等等（我试了很多东西，都记不清了。）

无论我尝试什么，我都会得到一个SQL错误

DBD::mysql::st execute failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''(type1, type2)'
    AND b.type = bt.type
 ) AS d
 WHERE distance <= radius'

DBD:：mysql:：st execute失败：您的SQL语法有错误；检查与您的MySQL服务器版本对应的手册，以了解在“”附近使用的正确语法（type1，type2）
b.type=bt.type
)AS d
如果距离，则需要在（…）

语句中的

中使用占位符。
execute（）。您可以创建动态占位符列表，如下所示：

my @types = qw(type1 type2);
my $placeholders = join ", ", ("?") x @types;
my $sql = "...
        b.typeID IN ($placeholders)
    ...";
my $points = $y->dbh->prepare($sql);
$results  = $points->execute($lat, $lng, $rad, $units, @types);

DBD::mysql::st execute failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''(type1, type2)'
    AND b.type = bt.type
 ) AS d
 WHERE distance <= radius'

my @types = qw(type1 type2);
my $placeholders = join ", ", ("?") x @types;
my $sql = "...
        b.typeID IN ($placeholders)
    ...";
my $points = $y->dbh->prepare($sql);
$results  = $points->execute($lat, $lng, $rad, $units, @types);