[PIG-1389] Implement Pig counter to track number of rows for each input files

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.7.0
• Fix Version/s: 0.8.0
• Hadoop Flags: Reviewed
• Assignee: Richard Ding
• Reporter: Richard Ding
• Created: 22/Apr/10 17:40
• Updated: 17/Dec/10 22:44
• Resolved: 09/Jul/10 22:47

Description

A MR job generated by Pig not only can have multiple outputs (in the case of multiquery) but also can have multiple inputs (in the case of join or cogroup). In both cases, the existing Hadoop counters (e.g. MAP_INPUT_RECORDS, REDUCE_OUTPUT_RECORDS) can not be used to count the number of records in the given input or output. PIG-1299 addressed the case of multiple outputs. We need to add new counters for jobs with multiple inputs.