ACID更新ElasticSearch文档

Question

I'm trying to build a Tinder-like system right now. Here I need to know which cards have already been seen.

If I save the cards in ElasticSearch, and then have such a document:

{ nama: David, location: {lat, lon}, seenFromUsers: [] }

I'm just wondering if it makes sense to create a list in the object itself. Probably there are 2000 entries in it. But if I do an update in ElasticSearch, then I always have to pass all 2000 entries. If two users do this at the same time, does one get lost? How can I simply add another ID to the array? Is that even possible?

What other solutions are there?

Answer 1

One other solution would be a complete different approach. Instead if creating documents like this

{
  "name": "David",
  "location": { "lat": ..., "lon": ...},
  "seenFromUsers": ["Laura", "Simone"]
}

think in Relations like this:

{
  "name": "David",
  "seenBy": "Laura"
}

{
  "name": "David",
  "seenBy": "Simone"
}

this approach will give you simpler queries, and the ACID problem is solved. New profile views are simply new documents...

As a benefit, you´ll get rid of inner objects and it will be more easy to add additional data to this relation:

{
  "name": "David",
  "seenBy": "Laura",
  "timestamp": ...,
  "liked": true
}

{
  "name": "David",
  "seenBy": "Simone",
  "timestamp": ...,
  "liked": false
}

And now you´ll be able to do a simple query for all positive likes of a profile, or bi-directional likes/matches...