> On 11.05.2018 18:01, Tatsuo Ishii wrote:
>> Plus checking username is neccessary (otherwise any user could
>> retrieve a cache for a table lookup which is not permitted by other
>> users).
>
> as the tables a cached query operated on is known anyway -- it's
> needed
> to purge cache entries when table content changes -- schema and table
> level SELECT privileges can be checked ... I'm not fully sure about
> how MySQL handles its column level privileges in that respect,
> something
> I'd need to try out ...
I am not talking about cache invalidation. If a cache entry is created
for a table which is only accessable by user A, the cache entry should
be hit for only A, not someone else. Otherwise it will be a serious
security problem.
Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp