16. 1. 1. The Analytical Functions in Oracle (Analytical Functions I) |
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The analytical functions fall into categories: |
- ranking,
- aggregate,
- row comparison,
- statistical.
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The function has this syntax: |
function() OVER() |
For example, SELECT RANK() OVER(ORDER BY salary) FROM employee |
The part may be empty, as it is in the above example: "RANK()." |
The contains an ordering, partitioning, or windowing clause. |
The ordering clause in the above example is "OVER(ORDER BY salary)." |
An analytical function that uses an ordering may also partition the result set based on some attribute value. |
The Row-numbering and Ranking Functions |
- ROW_NUMBER
- RANK
- DENSE_RANK
- PERCENT_RANK
- CUME_DIST
- NTILE
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