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Question
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
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Suppose you have created a data model for an airline based on a variety of forms, reports, user interviews, data sources, etc. Your client comes forward with a new desired report that includes passenger weights and a relationship between passengers and employees, neither of which is in your E-R diagram. You should ________.
A) create a new, separate E-R diagram with just the new information
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Q:
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Q:
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