Hi Jon, We need to keep tracking of all updates like 'User' of our platform can check what changes made before. I am thinking in this way.. CREATE TABLE book_info ( book_id uuid, book_title text, author_name text, updated_at timestamp, PRIMARY KEY(book_id)); This table will contain details about all book with unique updated details. CREATE TABLE book_title_by_user( book_title text, book_id uuid, user_id uuid , ts timeuuid, primary key(book_title,book_id,user_id,ts)); This table wil contain details of multiple old updates of book which can be done by mulplie users like MANY TO MANY .
What do you think on this? On Wed, May 17, 2017 at 9:44 AM, Jonathan Haddad <j...@jonhaddad.com> wrote: > I don't understand why you need to store the old value a second time. If > you know that the value went from A -> B -> C, just store the new value, > not the old. You can see that it changed from A->B->C without storing it > twice. > > On Tue, May 16, 2017 at 6:36 PM @Nandan@ <nandanpriyadarshi...@gmail.com> > wrote: > >> The requirement is to create DB in which we have to keep data of Updated >> values as well as which user update the particular book details and what >> they update. >> >> We are like to create a schema which store book info, as well as the >> history of the update, made based on book_title, author, publisher, price >> changed. >> Like we want to store what was old data and what new data updated.. and >> also want to check which user updated the relevant change. Because suppose >> if some changes not made correctly then they can check changes and revert >> based on old values. >> We are trying to make a USER based Schema. >> >> For example:- >> id:- 1 >> Name: - Harry Poter >> Author : - JK Rolling >> >> New Update Done by user_id 2:- >> id :- 1 >> Name:- Harry Pottor >> Author:- J.K. Rolls >> >> Update history also need to store as :- >> User_id :- 2 >> Old Author :- JK Rolling >> New Author :- J.K. Rolls >> >> So I need to update the details of Book which is done by UPSERT. But also >> I have to keep details like which user updated and what updated. >> >> >> One thing that helps define the schema is knowing what queries will be >> made to the database up front. >> Few queries that the database needs to answer. >> What are the current details of a book? >> What is the most recent update to a particular book? >> What are the updates that have been made to a particular book? >> What are the details for a particular update? >> >> >> Update frequently will be like Update will happen based on Title, name, >> Author, price , publisher like. So not very high frequently. >> >> Best Regards, >> Nandan >> >
