Hour 14, "Using Subqueries to Define Unknown Data"

Quiz Answers

1: What is the function of a subquery when used with a SELECT statement?
A1: The main function of a subquery when used with a SELECT statement is to return data that the main query can use to resolve the query.
2: Can you update more than one column when using the UPDATE statement in conjunction with a subquery?
A2: Yes, you can update more than one column using the same UPDATE and subquery statement.
3: Are the following syntaxes correct? If not, what is the correct syntax?
  1. SELECT CUST_ID, CUST_NAME
        FROM CUSTOMER_TBL
        WHERE CUST_ID =
                       (SELECT CUST_ID
                               FROM ORDERS_TBL
                               WHERE ORD_NUM = '16C17');
										
  2.  SELECT EMP_ID, SALARY FROM EMPLOYEE_PAY_TBL WHERE SALARY BETWEEN '20000' AND (SELECT SALARY ...

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