How to handle time zone issue without storing date time as TIMESTAMP WITH TIME ZONE
We are developing a mobile app that retrieve and display data from a legacy system.. In the legacy system the date time column is stored in Date data type, not TIMESTAMP WITH TIME ZONE. Now we need to handle time zone issue in the mobile app.
We want the time for data to reflect the time zone (offset to GMT) for the user that entered it (or at least be stored in GMT) so that we can interpret it properly on behalf of the user that views it.
Our "extreme case" situation is a legacy system user in time zone A entering orders for time zone A, the database server in time zone B, and a mobile app user in time zone C.