[PIG-4726] "Incompatable field schema" with MIN(datetime_field) and explicit output type

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 0.15.0
• Assignee: Unassigned
• Reporter: Nathan Smith
• Created: 04/Nov/15 04:32
• Updated: 04/Nov/15 07:27

Description

Example:

grunt> data = LOAD 'file.csv' USING PigStorage(',') AS (f1:chararray,f2:datetime);
grunt> earliest_datum = FOREACH (GROUP data ALL) GENERATE MIN(data.f2);
grunt> earliest_datum = FOREACH (GROUP data ALL) GENERATE MIN(data.f2) AS earliest;
grunt> describe earliest_datum;
earliest_datum: {earliest: datetime}
grunt> earliest_datum = FOREACH (GROUP data ALL) GENERATE MIN(data.f2) AS earliest:datetime;
2015-11-03 23:20:00,422 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1031: Incompatable field schema: declared is "earliest:datetime", infered is ":double"
grunt> earliest_datum = FOREACH (GROUP data ALL) GENERATE MIN(data.f2) AS earliest:double;
2015-11-03 23:20:07,454 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1031: Incompatable field schema: declared is "earliest:double", infered is ":datetime"

The example is contrived, but applying MIN to other field types in the same fashion seems to behave as expected.

Also affects MAX.