Explanation:The comparison operators are (<, ≤, =, =, >, ≥). 7. An expression in the domain relational calculus is of the form
A. {P(x1, x2, . . . , xn) | < x1, x2, . . . , xn > }
B. {x1, x2, . . . , xn | < x1, x2, . . . , xn > }
C. { x1, x2, . . . , xn | x1, x2, . . . , xn}
D. {< x1, x2, . . . , xn > | P(x1, x2, . . . , xn)}
Answer:A
Explanation:The comparison operators are (<, ≤, =, =, >, ≥). 7. An expression in the domain relational calculus is of the form
A. {P(x1, x2, . . . , xn) | < x1, x2, . . . , xn > } B. {x1, x2, . . . , xn | < x1, x2, . . . , xn > } C. { x1, x2, . . . , xn | x1, x2, . . . , xn} D. {< x1, x2, . . . , xn > | P(x1, x2, . . . , xn)}