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164. View the Exhibit and examine the structure of CUSTOMERS and SALES tables.

Evaluate the following SQL statement:

UPDATE (SELECT prod_id, cust_id, quantity_sold, time_id

FROM sales)

SET time_id = '22-MAR-2007'

WHERE cust_id = (SELECT cust_id

FROM customers

WHERE cust_last_name = 'Roberts' AND

credit_limit = 600);

Which statement is true regarding the execution of the above UPDATE statement?

A. It would not execute because two tables cannot be used in a single UPDATE statement.

B. It would not execute because the SELECT statement cannot be used in place of the table name.

C. It would execute and restrict modifications to only the columns specified in the SELECT statement.

D. It would not execute because a subquery cannot be used in the WHERE clause of an UPDATE statement.

Answer: C

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