Support new feature sync data before add a new row?

[hien_nguyen]

I wish Appsheet can check backend database berfore add new row to prenvent duplicate Key or orverwrittern data when users update in the same time.

[Aurelien]

Hi @hien_nguyen 

It actually does if you add a "valid_If" condition in order to avoid duplicates ?

More information here:

List expressions 

Last section "Use lists to validate column values"

Can you detail in which case that happens ?

[hien_nguyen]

Hi @Aurelien,

I mean Appsheet can check sync from datasource before add to avoid duplicate key. Althought I valid if for the key columns but if many user add a new in the same times, the system can not recognize it before they was using old data.