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<p><b><span style="font-size:22pt">Explaination 020: </span></b></p>
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This query shows correct JOIN ON clause syntax and provides equivalent to the above SQL statement. <br>
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Incorrect Answers <br>
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A: This statement will show data only for the EMPLOYEES table with records that have department ID from DEPARTMENTS table, not join result of two tables. <br>
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B: NATURAL join selects rows from the tables that have equal values in all matched columns (same column names). If the columns having the same names have different datatypes, an error is returned. <br>
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D: There is incorrect usage of JOIN clause with USING keyword. <br>
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OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 112-114 <br>
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Chapter 3: Advanced Data Selection in Oracle
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