必须使用exists子查询：

interface TodoRepository extends JpaRepository<Todo, String> {
  @Query("select t from Todo t left join fetch t.attachments attachment where exists (select 1 from t.attachments a where a.id in (:attachmentIds))")
  List<Todo> findAttachedTodos(List<String> attachmentIds);
}

如果您有一个联接表，那么可以使用一个联接表。如果我敢打赌这是一个可能的解决办法。应该用数据库列、表和其他变量替换这些名称。

@Entity
public class Todo { 
    // ...

    @ManyToMany(cascade = { CascadeType.ALL })
    @JoinTable(
        name = "todo_attachment", 
        joinColumns = { @JoinColumn(name = "todo_id") }, 
        inverseJoinColumns = { @JoinColumn(name = "attachment_id") }
    )
    private List<Attachment> attachments;

}

你的依恋实体应该是这样的：

@Entity
public class Attachment {    
    // ...  

    @ManyToMany(mappedBy = "attachments")
    private List<Todo> todos = new ArrayList<>();

}

进一步阅读多对多连接简介。