25 lines
631 B
Plaintext
25 lines
631 B
Plaintext
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Oracle's ``++ROWNUM++`` is a pseudo column that numbers the rows in a result set. Unfortunately, it numbers the rows in the set _before_ ordering is applied. So combining the two in the same query won't get you the results you expect. Instead, you should move your selection and ordering into a subquery, and use ``++ROWNUM++`` only on the outer query.
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== Noncompliant Code Example
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----
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SELECT fname, lname, deptId
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FROM employee
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WHERE rownum <= 10
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ORDER BY salary -- Noncompliant
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----
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== Compliant Solution
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----
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SELECT *
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FROM ( SELECT fname, lname, deptId
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FROM employee
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ORDER BY salary
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)
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WHERE rownum <= 10
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----
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