DatabasesBackendDevOps/Cloud
Replication
Also written as Read Replica, Primary-Replica
Keeping copies of a database's data on multiple servers, so reads can be spread across copies and the system stays available if one server fails.
Think of it like
Like a library keeping duplicate copies of a popular book at multiple branches, instead of forcing every reader to visit one central library.
Junior or senior?
Junior sounds like
Doesn't account for replication lag when reading from a replica.
Senior sounds like
Understands the lag and can describe a real bug it caused.
Ask them
“Has replication lag ever caused a real bug in your system? What happened?”