Description
Pig already has couple of map-side join implementations: Merge Join and Fragmented-Replicate Join. But both of them are pretty restrictive. Merge Join can only join two tables and that too can only do inner join. FR Join can join multiple relations, but it can also only do inner and left outer joins. Further it restricts the sizes of side relations. It will be nice if we can do map side joins on multiple tables as well do inner, left outer, right outer and full outer joins.
Lot of groundwork for this has already been done in PIG-1309. Remaining will be tracked in this jira.