Some system ideas to recap
- Database join & reading data from database
When fetching data from data base, we could have multiple DB query from client code to get different data we need, and then processing/union form the client side logic.
Another common trick around here, is to using 1 query with JOIN operation to push some of the work load to the database execution engine.
TODO: add some properties around join
MySQL is more friendly to join operation.
Inner join, outer join, left join, right join will produce different results.
2. Different ways of indexing, recap
3. cache inconsistency and cache invalidation
which request methods are natural for retry / idempotent. which request methods are checking for duplicate / how to handle user session or id inside request ./ different HTTP request / restful API version concept.
5. scale of number and their interchange? MB -> B, ns->s etc
6. file system VS database.
7. processing queue / encoding queue
8. video / music / photo related techniques.
9. parallel processing, split file in chunk and handling in parallel