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<p><b><span style="font-size:22pt">Explaination 029: &nbsp;</span></b></p>

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	Indexes are created automatically by Oracle to support integrity constraints that enforce uniqueness. The two types of integrity constraints that enforce uniqueness are PRIMARY KEY and UNIQUE constraints. When the primary key or UNIQUE constraint is declared, a unique index to support the column's uniqueness is also created, and all values in all columns that were defined as part of the primary key or UNIQUE constraint are placed into the index. <br>
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	  Incorrect Answers <br>
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	<p>
	  A: Oracle will not implicitly create an unique index for the NOT NULL constraint. <br>
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	  C: Oracle will not implicitly create an unique index for the FOREIGN KEY constraint. <br>
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	  D: Oracle will not implicitly create an unique index for the FOREIGN KEY constraint. <br>
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	  OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 237-238 <br>
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	<p>
	  Chapter 5: Creating Oracle Database Objects
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