使用sqlc生成db方法。有以下查询

-- name: RemoveRows:exec
DELETE FROM demotable
WHERE last_updated < (CURRENT_TIMESTAMP - INTERVAL '30' SECOND);

我想传递30作为参数，但我使用了下面的查询，然后引号不来，数据库给出错误。

-- name: RemoveRows:exec
DELETE FROM demotable
WHERE last_updated < (CURRENT_TIMESTAMP - INTERVAL $1 SECOND);

尝试引用$1，但sqlc认为它是字符串

-- name: RemoveRows:exec
DELETE FROM demotable
WHERE last_updated < (CURRENT_TIMESTAMP - INTERVAL '$1' SECOND);