56) Which of the following illustrates the authors’ preferred style of defining a primary key?
A) CREATE TABLE CUSTOMER (
CustomerID Integer Primary Key
LastName Char(35) Not Null
First Name Char(25) Null
);
B) CREATE TABLE CUSTOMER (
CustomerID Integer Not Null
LastName Char(35) Not Null
First Name Char(25) Null
CONSTRAINT CustomerPK PRIMARY KEY (CustomerID)
);
C) CREATE TABLE CUSTOMER (
CustomerID Integer Not Null
LastName Char(35) Not Null
First Name Char(25) Null
);
ALTER TABLE CUSTOMER
ADD CONSTRAINT CustomerPK PRIMARY KEY (CustomerID);
D) Both B and C are correct
57) Given the SQL statement:
CREATE TABLE SALESREP (
SalesRepNo int NOT NULL,
RepName char(35) NOT NULL,
HireDate date NOT NULL,
CONSTRAINT SalesRepPK PRIMARY KEY (SalesRepNo),
CONSTRAINT SalesRepAK1 UNIQUE (RepName)
);
We know that ________.
A) RepName is the primary key
B) RepName is a foreign key
C) RepName is a candidate key
D) RepName is a surrogate key