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User Friendship Schema Design

#ecto#schema
tnederlof

tnederlof

User Friendship Schema Design

I have been thinking of the most efficent way to setup a schema to take Users and associate them with one another when they “friend” each other. I found a thread from 2017 with some good ideas (Best-practise question - follow and friends posts in ecto), however there was some pretty intense queries that have to be done on the Friendship table (to check both directions). Is there a more efficient (from a querying perspective)? Right now I have a User and a Friendship schema where in Friendship there is a “friend_a_id” and a “friend_b_id”.

Any thoughts would be greatly appreciated!

8 comments
#ecto#schema
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First Post!

stefanchrobot

stefanchrobot

Two options come to mind:

  1. Store the friendship in sorted order, i.e. friend_a_id < friend_b_id. On the boundary of the context, always make sure to sort the ids before querying.
  2. Store the relationship twice. When unfriending, make sure to delete both entries.
Post #2

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