Backup copies are stored along with primary copies in the same storage and indexed by same indexes. As a matter of fact, any backup copy can become a primary copy at any moment of time due to topology change. Therefore, if there a scan, the amount of data you have to go through doubles when you add backup.
Providing hints is not a requirement, and most likely will not be needed for such a simple query. What I meant is that you should check the execution plan to verify indexes are applied as you expect: https://apacheignite.readme.io/docs/sql-performance-and-debugging#using-explain-statement -Val -- Sent from: http://apache-ignite-users.70518.x6.nabble.com/