[PIG-2526] Add ability to parametize keys in maps with tuple fields or scalars

• Type: New Feature
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.9.2
• Component/s: data, parser
• Labels: data happy map parameter parametize pig type
• Assignee: Unassigned
• Reporter: Russell Jurney
• Created: 10/Feb/12 23:06
• Updated: 11/Feb/12 00:38

Description

I want to access values in maps by tuple fields.

A = load 'data' as (id:int, M:map[]);
B = load 'other_data' as (id:int, cat:chararray);

C = JOIN A by id, C by id;
D = foreach A generate A:id, M#cat as hash_value; /* the value in cat for each record serves as the key in the map to retrieve its value. */