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<p><b><span style="font-size:22pt">Explaination 059: </span></b></p>
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INSTR returns the numeric position of a named character. DECODE translates an expression after comparing it to each search value. TRIM trims the heading of trailing characters (or both) from a character string. NULLIF compares twp expressions and returns null if they are equal, or the first expression if they are not equal. <br>
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Incorrect Answers <br>
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B: This statement is not correct. The following is the Syntax for NVL2 function: NVL2(expr1, expr2, expr3). If expr1 is not null, NVL2 returns expr2. If expr1 is null, NVL2 returns expr3. <br>
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C: Command TRUNCATE is used to remove all row data from the table, while leaving the definition of the table intact, including the definition of constraints and any associated database objects as indexes, constraints, and triggers on the table. <br>
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F: NVL returns second parameter value if first one is NULL.<br>
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OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 67-73 <br>
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Chapter 2: Limiting, Sorting, and Manipulating Return Data
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