Suppose you have Users with an email and name, and you want to search by both email and name.
What is the difference in performance between having two indexes (on email and name) and having one index on both fields?
I read the following but did not find the answer:
Multicolumn Indexes (PostgreSQL documentation)
Multicolumn index and performance (DBA Q & A)
PostgreSQL single vs. multi-column indexing for optimal SELECT performance (Stack Overflow)
Multiple column index vs multiple indexes (Percona)
I am interested in the difference in performance for Postgres and MongoDB.