I need to add a custom data field for insert citizen ID to the User. I am not sure if SDK provides this posibility. How can I check it? Or how can I add a custom data field?
We suppose you want to insert an extra data (citizen_ID) to User structure and then store it in database. You can achieve this by using either Tags (IEngine_SetIntTag(...), IEngine_SetStringTag(...)) or by setting Custom Data string (IEngine_SetCustomData(...)). Custom Data are similar to Tags, but Custom Data can store even binary data (photo, documents) with unlimited size. Also Custom Data string is not cached in memory - it is always loaded on demand from database. For more information please refer to the documentation.