RANK

Compatibility
RANK() OVER (ORDER BY f DESC)
Engine	OK	Alternative
ingres	No
mysql	No
oracle	Yes
postgres	No
sqlserver	Yes

RANK() OVER (ORDER BY f DESC) returns the rank position relative to the expression f.

  RANK() OVER (ORDER BY f DESC)

In this example we show the ranking, by population of those countries with a population of over 180 million.

SELECT name,population,
       RANK() OVER (ORDER BY population DESC)
       AS r
FROM world WHERE population>180000000
ORDER BY name

Using RANK OVER PARTITION

You can see view the RANK according to continent. This shows the biggest country

SELECT
 name,population,
 RANK() OVER (ORDER BY population DESC) AS world_rank,
 RANK() OVER (PARTITION BY continent ORDER BY population DESC) 
            AS local_rank
FROM world WHERE population>100000000
ORDER BY name