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	<b>QUESTION 171	</b>
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<p>Which two statements are true about constraints? (Choose two.) </p><table border="1" bordercolor="gray" width="665">
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			<p><b><input type="checkbox" name="AN" value="A">  A.</b></p>
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			<p> The UNIQUE constraint does not permit a null value for the column. 
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			<p><b><input type="checkbox" name="AN" value="B">  B.</b></p>
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			<p>   A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints. 
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			<p><b><input type="checkbox" name="AN" value="C">  C.</b></p>
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			<p>   The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index. 
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			<p><b><input type="checkbox" name="AN" value="D">  D.</b></p>
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			<p>   The NOT NULL constraint ensures that null values are not permitted for the column.</b></p>
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