How to give consecutive numbers to output records?

[Mark Kerzner]

Hi,

I need to number all output records consecutively, like, 1,2,3...

This is no problem with one reducer, making recordId an instance variable in
the Reducer class, and setting conf.setNumReduceTasks(1)

However, it is an architectural decision forced by processing need, where
the reducer becomes a bottleneck. Can I have a global variable for all
reducers, which would give each the next consecutive recordId? In the
database scenario, this would be the unique autokey. How to do it in
MapReduce?

Thank you