Q$2)$ Consider the following relations for a database that keeps track

of business trips of salespersons in a sales office:

SALESPERSON$($Ssn$,$ Name, Start$\_$year, Dept$\_$no$)$

TRIP$($Ssn$,$ From$\_$city, To$\_$city, Departure$\_$date, Return$\_$date, Trip$\_$id$)$

EXPENSE$($Trip$\_$id$,$ Account#$,$ Amount$)$

A trip can be charged to one or more accounts. Specify the foreign

keys for this schema, stating any assumptions you make.

Solution:

Open Microsoft $365($Office$)$

$($N$)$ viviates icicicinal micymily nevause Divuivi$-$ allu urere is

no tuple in the DEPARTMENT relation with DNUMBER$=2.$ We

may enforce the constraint by: $(1)$ relecting the insertion of the