Hi @GarethDoherty ,
Currently, within PowerApps, the Dynamics 365 for Fin & Ops connector is not a Delegable data source, so we could not delegate the data process within a canvas app to your Dynamics 365 for Fin & Ops data source. Delegation is not supported within Dynamics 365 for Fin & Ops data source.
As an alternative solution, you could consider bulk-load your Dynamics 365 for Fin & Ops data source records into multiple Collections within your app, then merge these collections into a Single one collection. Then use the merged Single one collection as data source within your app.
Please check and see if the alternative solution mentioned within following thread would help in your scenario:
https://powerusers.microsoft.com/t5/General-Discussion/Pulling-in-large-ish-SQL-tables/m-p/243777#M71518
In addition, as a better solution, you could consider add a corresponding Entity within the CDS of your PowerApps for your D365 for Fin & Ops table (the CDS Entity should have same data strature as your D365 for Fin & Ops table), then create a Data Integration project within your PowerApps, then use the Data Integration project to sync data from your D365 for Fin & Ops table into this CDS Entity.
More details about creating a Data Integration Project in PowerApps, please check the following article or video:
https://docs.microsoft.com/en-us/power-platform/admin/data-integrator
https://www.youtube.com/watch?v=UaSrnz2VMkE
After that, you could use the CDS Entity as data source within your app instead of the original D365 for Fin & Ops data source. The delegation is supported within Common Data Service (CDS), you could type a delegated Filter formula within your app to filter your CDS Entity records.
More details about the delegable functions or operators in Common Data Service connector, please check the following article:
https://docs.microsoft.com/en-us/connectors/commondataservice/
Best regards,
