The database is MongoDB.
If there is a data table (data -collection)— Users.
Every time a User updates his data, he needs to keep one copy of historical data, but not too much, for example, only the latest five copies.
If a table UserHistory is specially designed to store old data, it is necessary to judge whether there are more than 5 new records each time, and delete the oldest if there are more.
Is this reasonable?
Is there a more reasonable design?
https://docs.mongodb.com/v3.0 …
Can this document answer your questions?