Right now you can handle this with query hints. The plans are stable, but they are attached to the query text. When you throw a hint in there memsql generates a new plan since the query text changes.
To clarify - if you add the query hint, run the query, then remove the query hint then has the original query's plan expired?
Edit: I know I'm asking a lot about the plan cache, but as it's a core selling point, then I'd like to know how data distribution changes will affect performance. Stale queries will potentially adversley affect performance under certain circumstances.
