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BU.330.770.T2.FA25 Quiz 2- Requires Respondus LockDown Browser
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What is the correct SQL statement to add a ๐น ๐ ๐ ๐ธ ๐ผ ๐บ ๐ ๐พ ๐ธ ๐ constraint named ๐น ๐พ ๐ ๐ ๐ ๐ ๐ ๐ ๐ถ ๐ข ๐ โ ๐ ๐ ๐ ๐ on the ๐ถ ๐ข ๐ โ ๐ ๐ ๐ ๐ผ ๐ท column in the ๐ ๐ ๐ ๐ ๐ ๐ table, referencing the ๐ถ ๐ข ๐ โ ๐ ๐ ๐ ๐ผ ๐ท column in the ๐ถ ๐ข ๐ โ ๐ ๐ ๐ ๐ table?
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A.ALTER TABLE Orders ADD FOREIGN KEY (CustomerID)
REFERENCES Customers(CustomerID);
B.ALTER TABLE Orders ADD CONSTRAINT FK_Orders_Customers
REFERENCES Customers(CustomerID);
C.CREATE FOREIGN KEY FK_Orders_Customers ON Orders(CustomerID)
REFERENCES Customers(CustomerID);
D.ALTER TABLE Orders ADD CONSTRAINT FK_Orders_Customers FOREIGN KEY (CustomerID)
REFERENCES Customers(CustomerID);
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To determine the correct SQL statement for adding a foreign key constraint, I will evaluate each option step by step.
Option 1: 'ALTER TABLE Orders ADD FOREIGN KEY (CustomerID)\n\nREFERENCES Customers(CustomerID);' This statement is missing the 'CONSTRAINT <name>' clause, and while some RDBMSs allow 'ADD FOREIGN KEY' in isolation, the standard and most common syntax requires naming the constraint with 'ADD CONSTRAINT ......Login to view full explanation็ปๅฝๅณๅฏๆฅ็ๅฎๆด็ญๆก
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Question at position 28 Management has requested that you build an employee database. You need to include each employee's current position and salary, as well as all prior positions and salaries with the company. You decide to use a one-to-many structure: an employee table with the main information such as name and address, and an employment table with position and salary history. You can use the employeeID field to connect them. What is employment.employeeID an example of? primary key foreign key alternate key secondary key
Question at position 15 Management has requested that you build an employee database. You need to include each employee's current position and salary, as well as all prior positions and salaries with the company. You decide to use a one-to-many structure: an employee table with the main information such as name and address, and an employment table with position and salary history. You can use the employeeID field to connect them. What is employment.employeeID an example of? alternate key primary key secondary key foreign key
Question at position 13 Management has requested that you build an employee database. You need to include each employee's current position and salary, as well as all prior positions and salaries with the company. You decide to use a one-to-many structure: an employee table with the main information such as name and address, and an employment table with position and salary history. You can use the employeeID field to connect them. What is employment.employeeID an example of? primary key alternate key foreign key secondary key
A foreign key in a relational schema is based on ________ in ERD?
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