append two tables

hi, saranrajk 

It sounds like Incremental refresh in power bi.

https://docs.microsoft.com/en-us/power-bi/service-premium-incremental-refresh

Filter date column updates

The filter on the date column is used to dynamically partition the data into ranges in the Power BI service. Incremental refresh isn't designed to support cases where the filtered date column is updated in the source system. An update is interpreted as an insertion and a deletion, not an actual update. If the deletion occurs in the historical range and not the incremental range, it won’t get picked up. This can cause data refresh failures due to partition-key conflicts.

By the way, Incremental refresh is only for Power BI Premium for now.

Best Regards,

Lin