Example of the modulus partitioner

In this example, the modulus partitioner partitions a data set containing ten records. Four processing nodes run the partitioner, and the modulus partitioner divides the data among four partitions.

The input interface schema is as follows:

a:uint32; date:date;

Field a, of type uint32, is specified as the key field, on which the modulus operation is calculated.

Here is the input data set. Each line represents a record:

64123 1960-03-30
61821 1960-06-27
44919 1961-06-18
22677 1960-09-24
90746 1961-09-15
21870 1960-01-01
87702 1960-12-22
4705  1961-12-13
47330 1961-03-21
88193 1962-03-12

The following table shows the output data set divided among four partitions by the modulus partitioner.

Here are three sample modulus operations, corresponding to the values of the three key fields shown above with underscore:

22677 mod 4 = 1; the data is written to Partition 1.
47330 mod 4 = 2; the data is written to Partition 2.
64123 mod 4 = 3; the data is written to Partition 3.

None of the key fields can be divided evenly by 4, so no data is written to Partition 0.