问题
I have a list of ids that looks something like this:
feed_ids = [1,2,3,4,5] # will be filled with random ids
I have a Post model that has an attribute parent_ids that might look something like this:
parent_ids = [20,14,1]
I want to retrieve all records where an element in parent_ids matches an element in feed_ids
I tried this but it's not working:
nodes = Post.where(parent_ids: feed_ids)
It's not giving me an error but it's also not returning any records.
回答1:
The find method can take in an array. You could use array intersection here.
Post.find(parent_ids & feed_ids)
Disclaimer
I do not have Rails installed, so I have to go by my instinct.
Also, this might not be the most efficient solution if you have a large data-set. But with relatively few records, it should be fine.
来源：https://stackoverflow.com/questions/38235463/rails-4-activerecord-where-any-element-in-one-array-is-in-another-array