Difference between group and cogroup in Pig Latin
| Group | Cogroup |
|---|---|
| For readability GROUP is used in statements involving one relation |
Cogroup used as a statements involving two or more relations. Cogroup should no exceed 127 relations at a time. |
| The group statement collects together records with the same key |
cogroup is a general statement of group. Instead of collecting records of 1 input it collects records of N inputs based on a key |
| Syntax: grunt> Group_data = GROUP Relation_name BY age; |
Syntax: alias = CROSS alias, alias [, alias …] [PARTITION BY partitioner] [PARALLEL n]; |
