Discuss the different architectural models for Database-as-a-service.

In a(n) ____________________ attack, the attacker eavesdrops on the victim's session and uses statistical analysis of patterns and inter-keystroke timings to discern sensitive session information.

Fill in the blank(s) with the appropriate word(s).

A(n)____ operator compares two items and the result has a Boolean value.

A. complex B. relational C. unary D. remainder