Package org.apache.flink.table.api

Class Over

java.lang.Object
org.apache.flink.table.api.Over
@PublicEvolving public final class Over extends Object
Helper class for creating an over window. Similar to SQL, over window aggregates compute an aggregate for each input row over a range of its neighboring rows.

Java Example: 


 Over.partitionBy("a").orderBy("rowtime").preceding("unbounded_range").as("w")

Scala Example: 


 Over partitionBy 'a orderBy 'rowtime preceding UNBOUNDED_RANGE as 'w

  • Constructor Details

    • Over

      public Over()

  • Method Details

    • partitionBy

      public static OverWindowPartitioned partitionBy(org.apache.flink.table.expressions.Expression... partitionBy)
      Partitions the elements on some partition keys.

      Each partition is individually sorted and aggregate functions are applied to each partition separately.

      Parameters:
      partitionBy - list of field references
      Returns:
      an over window with defined partitioning

    • orderBy

      public static OverWindowPartitionedOrdered orderBy(org.apache.flink.table.expressions.Expression orderBy)
      Specifies the time attribute on which rows are ordered.

      For streaming tables, reference a rowtime or proctime time attribute here to specify the time mode.

      For batch tables, refer to a timestamp or long attribute.

      Parameters:
      orderBy - field reference
      Returns:
      an over window with defined order