[PIG-5335] Error message from range projection completely misleading

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.18.0
• Hadoop Flags: Reviewed
• Assignee: Koji Noguchi
• Reporter: Koji Noguchi
• Created: 10/Apr/18 14:29
• Updated: 15/May/18 04:21
• Resolved: 15/May/18 04:21

Description

A = load 'input.txt' as (a0,a1,a2,a3);
B = FOREACH A GENERATE a0, a1, a2, a3;
store B into '/tmp/deleteme';

C = FOREACH A GENERATE a0, b1, a2, a3;
D = FOREACH C GENERATE a0..a2;
(end of script, no store, nothing)

Error message

2018-04-10 10:22:33,360 [main] ERROR org.apache.pig.PigServer - exception during parsing: Error during parsing. Invalid field projection. Projected field [a0] does not exist in schema: a0:bytearray,a0:bytearray,a2:bytearray,a3:bytearray.

At least two issues.

1. Error should be about FOREACH for C referencing non-existing field 'b1'. But the error message is saying something about 'a0'.
2. Script itself is not using relation C and D at all. It's confusing to see errors coming out of unused relations.