为什么GAE DataStore不支持对不同属性的多个不等式过滤器？

Question

我知道这是DataStore的限制,但我只想弄清楚原因.我读过bigtable文章,我找不到对不同列上的不等式过滤器的任何限制.它可以支持前缀和范围扫描.恕我直言,DataStore可以通过这两个操作支持多个不等式过滤器.你知道从DataStore获取功能的任何原因吗？

Answer 1

To avoid having to scan the entire index table, the query mechanism relies on 
all of a query's potential results being adjacent to one another in the index.
To satisfy this constraint, a single query may not use inequality comparisons 
(LESS_THAN, LESS_THAN_OR_EQUAL, GREATER_THAN, GREATER_THAN_OR_EQUAL, NOT_EQUAL)
on more than one property across all of its filters

[来源:https://cloud.google.com/appengine/docs/standard/java/datastore/query-restrictions ]