equivalent of oracle rank() in postgres

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font-family:Courier">Hi,</span></font><p class="MsoNormal"><font face="Courier" size="3"><span style="font-size:12.0pt;
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font-family:Courier">Jus wanted the equivalent for rank() as in tis example..</span></font><p class="MsoNormal"><font
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font-family:Courier">SELECT *<br /> FROM (<br />   SELECT employee_id, last_name, salary,<br />   RANK() OVER (ORDER BY
salaryDESC) EMPRANK<br />   FROM employees)<br /> WHERE emprank = 3;</span></font><p class="MsoNormal"><font
face="Courier"size="3"><span style="font-size:12.0pt; 
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font-family:Courier">Rgds,</span></font><p class="MsoNormal"><font face="Courier" size="3"><span
style="font-size:12.0pt;
font-family:Courier">Chandan</span></font><font face="Arial" size="2"><span
style="font-size:10.0pt;font-family:Arial"></span></font></div>