hallo @Benedict cruz 

check Light BPT may help

https://www.outsystems.com/videos/how-to-use-light-bpt-for-parallel-processing/

https://success.outsystems.com/documentation/11/building_apps/data_management/mobile_performance_strategies_and_offline_optimization/implementing_offline_sync/

https://success.outsystems.com/documentation/11/building_apps/data_management/mobile_performance_strategies_and_offline_optimization/handling_optimized_complex_synchronization_on_mobile_devices/

and also sync example

https://www.outsystems.com/forums/discussion/96328/need-help-in-sync-logic-outsystems-reactive-application/

Hello @Benedict cruz,

I strongly recommend visiting the following links they should be very helpful: 

Offline Data Sync Patterns

Local Storage Entities

Data Synchronization Overview

Also refer to this component it gives you an example for all the Data sync patterns:

Offline Data Sync Patterns

Hello.

You should reasd the link given above, but a few small rules:

First, you need to optimize your local database.

• No useless atributes.
• No normal format. Minimize the joins you need.

Then you need to optimize the sync.

• Many small tables? Maybe a single fetch to the server can get them as once.
• Large table? Pull data in blocks, not megabytes at once.

If you can start working before all data was fetched, do it- Keep the user distracted while more data arrives.

One tip that is not on the manuals is to do a progress screen like in games.

As long as you say users "Table 3 of 20" they immediately stress less as they can manage their time.

@Karan Shinde ,

agree that in general, bulk is faster than single and that each server call adds overhead.

But be carefull about 2 things :

* don't give too definitive answers about things you don't know, for example, we don't know enough about the data and amount of records to just say splitting in just 2 server calls is the solution

* make sure your asnwers are consistent, or make clear what parts of your answer are alternatives to each other, now you are advising to both clear the local table and "also" only retrieve the changed records