[PIG-1112] FLATTEN eliminates the alias

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.9.0
• Assignee: Daniel Dai
• Reporter: Ankur Bansal
• Created: 26/Nov/09 08:00
• Updated: 04/Aug/11 00:34
• Resolved: 10/Jan/11 22:29

Description

If schema for a field of type 'bag' is partially defined then FLATTEN() incorrectly eliminates the field and throws an error.
Consider the following example:-

A = LOAD 'sample' using PigStorage() as (first:chararray, second:chararray, ladder:bag{});
B = FOREACH A GENERATE first,FLATTEN(ladder) as third,second;
C = GROUP B by (first,third);

This throws the error
ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1000: Error during parsing. Invalid alias: third in

{first: chararray,second: chararray}

Issue Links

• relates to: PIG-998 revisit frontend logic and pig-latin semantics