Исходное сообщение
"CryptDB - проект по обеспечению надежного шифрования данных ..." Отправлено Аноним, 20-Дек-11 15:55
> 1. нельзя использовать "salary > age*2+10", но можно "salary > age" или "salary > 10" > Это как так? Если "salary>age" и "salary>10" катит, значит значения обоих полей нам > известны. Что мешает произвести над известными значениями мат.операцию? For example, it does not support both computation and comparison on the same column, such as WHERE salary > age*2+10. CryptDB can process a part of this query, but it would also require some processing on the proxy. In CryptDB, such a query should be (1) rewritten into a sub-query that selects a whole column, SELECT age*2+10 FROM . . ., which CryptDB computes using HOM, and (2) re-encrypted in the proxy, creating a new col- umn (call it aux) on the DBMS server consisting of the newly en- crypted values. Finally, the original query with the predicate WHERE salary > aux should be run. We have not been affected by this limitation in our test applications (TPC-C, phpBB, HotCRP, and grad-apply).