org.jooq

Interface OrderedAggregateFunctionOfDeferredType

public interface OrderedAggregateFunctionOfDeferredType

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

Method Summary

Modifier and Type	Method and Description
<T> AggregateFilterStep<T>	withinGroupOrderBy(OrderField<T> field) Add an WITHIN GROUP (ORDER BY ..)

Method Detail

withinGroupOrderBy

@Support(value=POSTGRES_9_4)
<T> AggregateFilterStep<T> withinGroupOrderBy(OrderField<T> field)

Add an WITHIN GROUP (ORDER BY ..) clause to the ordered aggregate function