When you use SQL statements to access tables in a database without an index configured, a full table scan will
be performed. If a table contains a large amount of data, this kind of scan will access a large amount of data
and consume a lot of the database's resources. Which of the following options are best practices when creating
database indexes? (Number of correct answers: 3)
A developer has written a web application using a microservice architecture,
in such an architecture, the client (web browser or mobile application) first initiates a request. The request first
reaches the load balancer, then goes through an authentication service, a billing service, then requests a
resource, and finally a result is returned. How many spans does such a call chain
consist of?