Query cache and LinqService/RemoteDataContext thread safety.

[limpalex]

Query objects are not thread-safe. If multiple thread get the same instance they may change each other query parameter values.
Possible solutions (checked):

• Locking the Query object
• Marking Query._first field as ThreadStatic, so multiple threads will effectively have independent query cache.

I am not really satisfied with both of these solutions, so I'd like to know your opinion about this problem.

The bug can be noticed only when using LinqService and RemoteDataContext, so I guess there is something wrong with them.

Code example: http://pastebin.com/Vc6eaHry Here I'm trying to find entity by identifier and then checking that identifier is correct.

[limpalex]

Identical test for linq2db passed successfully, if that helps.