Module org.jooq
Package org.jooq

Interface OrderedAggregateFunction<T>

public interface OrderedAggregateFunction<T>
An ordered-set aggregate function.

An ordered-set aggregate function is an aggregate function with a mandatory Oracle-specific WITHIN GROUP (ORDER BY …) clause. An example is LISTAGG: 


 SELECT   LISTAGG(TITLE, ', ')
          WITHIN GROUP (ORDER BY TITLE)
 FROM     T_BOOK
 GROUP BY AUTHOR_ID
The above function groups books by author and aggregates titles into a concatenated string.

Ordered-set aggregate functions can be further converted into window functions using the OVER(PARTITION BY …) clause. For example: 


 SELECT LISTAGG(TITLE, ', ')
        WITHIN GROUP (ORDER BY TITLE)
        OVER (PARTITION BY AUTHOR_ID)
 FROM   T_BOOK
Author:
Lukas Eder