How to produce rank in Oracle
Need to rank the below by salary, with highest salary having rank 1.
The RANK
column shown is what I'm after:
Empname sal address RANK
----------------------------------------------
Ram 3411 45,east road 2
Anirban 2311 34,w开发者_StackOverflow中文版est wind 4
Sagor 10000 34,south 1
Manisha 3111 12,d.h road 3
Oracle10g means you can use analytic/ranking/windowing functions like ROW_NUMBER:
SELECT t.empname,
t.sal,
t.address,
ROW_NUMBER() OVER (ORDER BY t.sal DESC) AS RANK
FROM TABLE t
For the pedantic, replace ROW_NUMBER
with DENSE_RANK if you want to see ties get the same rank value:
If two employees had the same salary, the RANK function would return the same rank for both employees. However, this will cause a gap in the ranks (ie: non-consecutive ranks). This is quite different from the dense_rank function which generates consecutive rankings.
The old school means of ranking is to use:
SELECT t.empname,
t.sal,
t.address,
(SELECT COUNT(*)
FROM TABLE x
WHERE x.sal <= t.sal) AS RANK
FROM TABLE t
The output will match the DENSE_RANK output -- ties will have the same rank value, while being numbered consecutively.
Take a look at rank - samples here.
I often refer to this detailed, informative yet quick link Analytical Functions for the analytical functions.
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