📄 que_021.htm
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<title>Ocp test </title>
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<b>QUESTION 021
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<p>The EMP table contains these columns:</p><table border="1" bordercolor="gray">
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<p><b>EMP table </b></p>
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<p><b>LAST NAME VARCHAR2(25) </b></p>
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<p><b>SALARY NUMBER(6,2) </b></p>
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<p><b>DEPARTMENT_ID NUMBER(6) </b></p>
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<p>You need to display the employees who have not been assigned to any department. <br>
You write the SELECT statement:
<br><br>SELECT LAST_NAME, SALARY, DEPARTMENT_ID <br>
FROM EMP <br>
WHERE DEPARTMENT_ID = NULL; <br>
<br>What is true about this SQL statement?</p><table border="1" bordercolor="gray" width="665">
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<p><b><input type="radio" name="AN" value="A"> A.</b></p>
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<p> The SQL statement displays the desired results.
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<p><b><input type="radio" name="AN" value="B"> B.</b></p>
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<p> The column in the WHERE clause should be changed to display the desired results.
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<p><b><input type="radio" name="AN" value="C"> C.</b></p>
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<p> The operator in the WHERE clause should be changed to display the desired results.
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<p><b><input type="radio" name="AN" value="D"> D.</b></p>
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<p> The WHERE clause should be changed to use an outer join to display the desired
results.</p>
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