如何在连接列上查询distinct？

Question

这是代码,我想让UserCheckpoint.checkpoint有所区别.这意味着查询的所有UserCheckpoints都应具有不同的Checkpoint对象.

friends_ucp = (db.session.query(UserCheckpoint).
               join(UserCheckpoint.checkpoint).
               filter(radius_cond).
               filter(Checkpoint.demo == False).
               filter(UserCheckpoint.user_id.in_(friends))
               )

我该怎么做？谢谢.

Answer 1

我解决了这个问题 group_by()