Prashant Kommireddi created PIG-4724: ----------------------------------------
Summary: GROUP ALL must create an output record in case there is no input Key: PIG-4724 URL: https://issues.apache.org/jira/browse/PIG-4724 Project: Pig Issue Type: Bug Affects Versions: 0.15.0 Reporter: Prashant Kommireddi {code} A = load 'data'; B = filter A by $0 == 'THIS_DOES_NOT_EXIST'; C = group A ALL; D = foreach C generate group, COUNT(B); {code} Even if the filter did not output any rows, since we are grouping on ALL the expected output should probably be (ALL, 0). The implementation generates a pseudo key “all” for every input on map side, thus reduce side we can combine all input together. However, this does not work for 0 input since the reduce side does not get any input. If the input is empty, yield a pseudo “all, 0” to reduce -- This message was sent by Atlassian JIRA (v6.3.4#6332)