Question

Write a robust schema to remove a company and associated information from the UBER eats database. F. Produce a Z specification for card information that includes the information about account numbers, name, expiry date and CVV numbers

Answer 1

Robust schema to remove a company and associated information from the UBER eats database:

Remove Company

DCompanyBook

Name? : Person

Email? : EMAIL

Phone_no? : PHONE

Location? : ADDRESS

Phone_no ∈ dom(cb)

CompanyBook’ = { Phone_no? } CompanyBook

Z specification for card information including the information about account number, name, expiry date and CVV number:

DCardDetailBook

account numbers? : Number

name? : Person

expiry date ? : DATE

CVV number? : Number

account numbers? Ï dom(cdb)

CardDetailBook’ = CardDetailBook U { account numbers? -> name? -> expiry date ? ->CVV number?}