org.apache.flink.table.api

Interface WindowGroupedTable

@PublicEvolving
public interface WindowGroupedTable

A table that has been windowed and grouped for GroupWindows.

Method Summary

Modifier and Type	Method and Description
AggregatedTable	aggregate(org.apache.flink.table.expressions.Expression aggregateFunction) Performs an aggregate operation on a window grouped table.
AggregatedTable	aggregate(String aggregateFunction) Performs an aggregate operation on a window grouped table.
FlatAggregateTable	flatAggregate(org.apache.flink.table.expressions.Expression tableAggregateFunction) Performs a flatAggregate operation on a window grouped table.
FlatAggregateTable	flatAggregate(String tableAggregateFunction) Performs a flatAggregate operation on a window grouped table.
Table	select(org.apache.flink.table.expressions.Expression... fields) Performs a selection operation on a window grouped table.
Table	select(String fields) Performs a selection operation on a window grouped table.

Method Detail

select

Table select(String fields)

Performs a selection operation on a window grouped table. Similar to an SQL SELECT statement. The field expressions can contain complex expressions and aggregations.

Example:

 
   windowGroupedTable.select("key, window.start, value.avg as valavg")
 
 

select

Table select(org.apache.flink.table.expressions.Expression... fields)

Performs a selection operation on a window grouped table. Similar to an SQL SELECT statement. The field expressions can contain complex expressions and aggregations.

Scala Example:

 
   windowGroupedTable.select('key, 'window.start, 'value.avg as 'valavg)
 
 

aggregate

AggregatedTable aggregate(String aggregateFunction)

Performs an aggregate operation on a window grouped table. You have to close the aggregate(String) with a select statement. The output will be flattened if the output type is a composite type.

Example:

 
   AggregateFunction aggFunc = new MyAggregateFunction();
   tableEnv.registerFunction("aggFunc", aggFunc);
   windowGroupedTable
     .aggregate("aggFunc(a, b) as (x, y, z)")
     .select("key, window.start, x, y, z")
 
 

aggregate

AggregatedTable aggregate(org.apache.flink.table.expressions.Expression aggregateFunction)

Performs an aggregate operation on a window grouped table. You have to close the aggregate(Expression) with a select statement. The output will be flattened if the output type is a composite type.

Scala Example:

 
   val aggFunc = new MyAggregateFunction
   windowGroupedTable
     .aggregate(aggFunc('a, 'b) as ('x, 'y, 'z))
     .select('key, 'window.start, 'x, 'y, 'z)
 
 

flatAggregate

FlatAggregateTable flatAggregate(String tableAggregateFunction)

Performs a flatAggregate operation on a window grouped table. FlatAggregate takes a TableAggregateFunction which returns multiple rows. Use a selection after flatAggregate.

Example:

 
   TableAggregateFunction tableAggFunc = new MyTableAggregateFunction();
   tableEnv.registerFunction("tableAggFunc", tableAggFunc);
   windowGroupedTable
     .flatAggregate("tableAggFunc(a, b) as (x, y, z)")
     .select("key, window.start, x, y, z")
 
 

flatAggregate

FlatAggregateTable flatAggregate(org.apache.flink.table.expressions.Expression tableAggregateFunction)

Performs a flatAggregate operation on a window grouped table. FlatAggregate takes a TableAggregateFunction which returns multiple rows. Use a selection after flatAggregate.

Scala Example:

 
   val tableAggFunc = new MyTableAggregateFunction
   windowGroupedTable
     .flatAggregate(tableAggFunc('a, 'b) as ('x, 'y, 'z))
     .select('key, 'window.start, 'x, 'y, 'z)