[PIG-900] ORDER BY syntax wrt parentheses is somewhat different than GROUP BY and FILTER BY

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Xuefu Zhang
• Reporter: David Ciemiewicz
• Created: 03/Aug/09 18:34
• Updated: 05/Oct/11 00:02

Description

With GROUP BY, you must put parentheses around the aliases in the BY clause:

B = group A by ( a, b, c );

With FILTER BY, you can optionally put parentheses around the aliases in the BY clause:

B = filter A by ( a is not null and b is not null and c is not null );

However, with ORDER BY, if you put parenthesis around the BY clause, you get a syntax error:

 A = order A by ( a, b, c );

Produces the error:

2009-08-03 18:26:29,544 [main] ERROR org.apache.pig.tools.grunt.Grunt -
ERROR 1000: Error during parsing. Encountered " "," ", "" at line 3, column 19.
Was expecting:
    ")" ...

This is an annoyance really.

Here's my full code example ...

A = load 'data.txt' using PigStorage as (a: chararray, b: chararray, c: chararray );

A = order A by ( a, b, c );

dump A;

Issue Links

• depends upon: PIG-1618 Switch to new parser generator technology