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<p><b><span style="font-size:22pt">Explaination 082: </span></b></p>
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<span style="font-size:18pt">Statement in this answer will show correct results because usage of operator LIKE and format mask '_A%' extract the last names of those employees who have the letter "A" as the second character in their names. Symbol '_' in format mask substitute exactly one symbol and cannot be NULL. <br>
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<span style="font-size:18pt">Incorrect Answers <br>
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<span style="font-size:18pt">B: This statement will return only names starting from symbol '*'. It cannot be used as substitution symbol. <br>
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<span style="font-size:18pt">C: Usage of equity operator here is not appropriate in this case: query will look exact for first symbol '_', it will not be considered as substitution symbol. <br>
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<span style="font-size:18pt">D: This statement will return only names starting from symbol '*'. It cannot be used as substitution symbol.<br>
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OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 61-67
Chapter 2: Limiting, Sorting, and Manipulating Return Data </span></p>
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