Hi, I need a little help with someting I'd like to implement, but not sure how to do it.
Image classifieds site like eBay. There are a lot of filters there: by price, by category, by city, by condition...
Let's say we have this use case:
- User is able to search eBay using filters
- Once he does it he can save those filters and subscribe to get push notification when someone submits an ad that matches those filters
- I save those filters in my database for that user
For this example let's say that site has around 100k active subscriptions.
The first step is obviously to attack a place in a code where ad is being saved to the database. I'm having a problem with how to know if that specific ad matches those filters.
I would need to go through 100k subscriptions and their filters to know which filter matches the ad that has been posted. It doesn't sound too good for me, it could be 1M filters or more.
Can someone help me with that? What would be the best way to solve the problem?
What I have tried:
I tried to through 100k of records and execute filters to see if ad matches. That doesn't work