Optimization of the import process. How to do?

Question

PHP

Good afternoon. At the interview, they asked a task for perception, which was stumped. If someone has an idea - please share)
So. There is an online store. The load averages 2000 hits per second. In the store, once every 1.5 hours, data is imported (updating balances in warehouses). The export duration is 30 seconds. How to achieve the result so that relevant information is available instantly. I don't know, maybe the question is not quite correct (I'm a beginner developer).

Answer 1

instantly and import in 30 seconds are incompatible concepts, the task requires clarification.
if the question is that the actual data should be available at once (not gradually as the import is performed), then look at transactions or create a new database and switch to it in the config at the end of the import.