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<p><b><span style="font-size:22pt">Explaination 089: </span></b></p>
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For N joined tables using Oracle or ANSI/ISO syntax for table joins, you need at least N-1 equijoin conditions in the WHERE clause of your SELECT statement or N-1 JOIN table_name ON join_condition clauses in order to avoid a Cartesian product, respectively. <br>
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Incorrect Answers <br>
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A: There is no maximum on two tables to join them through an equijoin. <br>
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B: There is no maximum on two columns to join them through an equijoin. <br>
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C: You can specify an equijoin condition only in the FROM clauses of a SELECT statement. <br>
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D: There is no limitation about primary key and foreign key for the columns to use them for an equijoin. <br>
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OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 99-107 <br>
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Chapter 3: Advanced Data Selection in Oracle
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