I understand that a lot of similar questions have already been asked but i could not find a definitive answer for my question.
In very short,
I have to authenticate users using a rest api and using their phone numbers.
phone numbers are fixed length (10). can be stored in any way suggested.
In a table with thousands of phone numbers and the user_id associated, i wish to be able to query and get the user_id associated with the phone number fast.
I read that indexing on strings or random integers is bad.
How should i structure the db to query on phone number most effectively?
Thanks in advance!