elasticsearch/elasticsearch — pull request #5970 by martijnvg (2014-04-29 08:42:25+00:00)
Title: Add global ordinal based implementations for significant terms aggregation

Add global ordinals based significant terms aggregation.
Just as in terms aggregation the significant terms aggregation has two new execution hints: `global_ordinals` and `global_ordinals_hash`.

For top / single significant terms `global_ordinals` is the default execution hint and for sub significant terms `global_ordinals_hash` is the default execution hint.