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<p><b><span style="font-size:22pt">Explaination 004: </span></b></p>
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These answers show correct syntax, because they use ANY and ALL keywords for convert multi-row output of sub-query to one-row result. <br>
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Incorrect Answers <br>
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A: This SELECT statement is incorrect because of multi-row return of sub-query: it will return minimal salary for EACH department. <br>
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B: This SELECT statement is incorrect because of multi-row return of sub-query: it will return average salary for EACH department. <br>
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F: This SELECT statement is incorrect because GROUP BY clause cannot contain functions,like AVG(), MIN(), MAX() and so on. <br>
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OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 145-156 <br>
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Chapter 4: Subqueries
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