Exercise 2.2.1a
For relation Accounts, the attributes are:
acctNo, type, balance
For relation Customers, the attributes are:
firstName, lastName, idNo, account
Exercise 2.2.1b
For relation Accounts, the tuples are:
(12345, savings, 12000),
(23456, checking, 1000),
(34567, savings, 25)
For relation Customers, the tuples are:
(Robbie, Banks, 901-222, 12345),
(Lena, Hand, 805-333, 12345),
(Lena, Hand, 805-333, 23456)
Exercise 2.2.1c
For relation Accounts and the first tuple, the components are:
123456 � acctNo
savings � type
12000 � balance
For relation Customers and the first tuple, the components are:
Robbie � firstName
Banks � lastName
901-222 � idNo
12345 � account
Exercise 2.2.1d
For relation Accounts, a relation schema is:
Accounts(acctNo, type, balance)
For relation Customers, a relation schema is:
Customers(firstName, lastName, idNo, account)
Exercise 2.2.1e
An example database schema is:
Accounts (
acctNo,
type,
balance
Customers (
firstName,
lastName,
idNo,
account
Exercise 2.2.1f
A suitable domain for each attribute:
acctNo � Integer
type � String
balance � Integer
firstName � String
lastName � String
idNo � String (because there is a hyphen we cannot use Integer)
account � Integer
Exercise 2.2.1g
Another equivalent way to present the Account relation:
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