Increase running time of statement. Fixes #963.

The time between starting the statement and calling the future is
arbitrary. Now the execution time of the statement is very very long.
This ensures that the statement is not already finished when the
future is called.
I worry that this value might cause problems in some implementations. Could we just use `60 * 60L * 1000L` and rename this to `ONE_HOUR_MILLIS`?