IHP -如何使用多个collectionFetchRelated？

Question

我有以下注释模式：

Table: Comments
Columns: id, post_id, body, user_id, created_at

我想获取评论与其各自的帖子和用户。

对一列使用collectionFetchRelated很简单：

comments <- query @Comment 
  |> fetch
  >>= collectionFetchRelated #postId

它很容易被称为，

Include "postId" Comment

但是如何使用它并调用多列呢？

Answer 1

你应该能够做到这一点：

comments :: [Include' ["postId", "userId"] Comment] <- query @Comment 
  |> fetch
  >>= collectionFetchRelated #postId
  >>= collectionFetchRelated #userId

Include' ["postId", "userId"] Comment类型只是Include "userId" (Include "postId" (Comment))的缩写