Refreshing data without overwritting the existing one

Hello,

I would like to refresh data I get from REST API in a certain way. Let me explain :

Assuming my data is initally like this :

Index     Type        Today's date

1            A             12/02/2021

2            B             12/02/2021

3            C             12/0/2021

I would like to make sure that after refreshing, my existing data won't be replaced but will be organized like this :

Index      Type      Today's date

1             A           12/02/2021

2             B           12/02/2021

3             C           12/02/2021

4             D           15/02/2021

1             A           16/02/2021

For now, the type A row is overwritten et and the "today's date" field is replaced by the new one. 

Is it possible to prevent this and to append a new type A row with a new today's date (keeping both rows).

Thank you by advance,

Best.