You can do two passes of the data. The first map-reduce pass is sanity checking the data. The second map-reduce pass is to do the real work assuming the first pass accept the file.
You can utilize the dynamic counter and define an enum type for error record categories. In the mapper, you parse each line, and use the result to update the counter. -Mingxi From: Mapred Learn [mailto:mapred.le...@gmail.com] Sent: Monday, November 14, 2011 3:06 PM To: mapreduce-user@hadoop.apache.org Subject: how to implement error thresholds in a map-reduce job ? Hi, I have a use case where I want to pass a threshold value to a map-reduce job. For eg: error records=10. I want map-reduce job to fail if total count of error_records in the job i.e. all mappers, is reached. How can I implement this considering that each mapper would be processing some part of the input data ? Thanks, -JJ