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Hive with python conversion function: "cannot recognize input next to" transform "error

I have a Hive table that keeps track of the state of an object moving through process steps. The table looks like this:

hive> desc journeys;
object_id           string                                      
journey_statuses    array<string>

Here is a typical recording example:

12345678    ["A","A","A","B","B","B","C","C","C","C","D"]

Entries in the table were generated using Hive 0.13 collect_list, and the statuses are in order (if the order is not important, I would use it collect_set). For each object_id, I would like to shorten the trip in order to return the statuses of the path in the order in which they appear.

I wrote a quick Python script that reads from stdin:

#!/usr/bin/env python
import sys
import itertools

for line in sys.stdin:
    inputList = eval(line.strip())
    readahead = iter(inputList)
    next(readahead)
    result = []
    for id, (a, b) in enumerate(itertools.izip(inputList, readahead)):
        if id == 0:
          result.append(a)
        if a != b:
          result.append(b)
    print result

I planned to use this in a Hive call transform. It seems to work on local startup:

$ echo '["A","A","A","B","B","B","C","C","C","C","D"]' | python abbreviate_list.py
['A', 'B', 'C', 'D']

However, when I add a file and try to execute inside Hive, an error is returned:

hive> add file abbreviateList.py;                                                                           
Added resource: abbreviateList.py

hive> select
    >   object_id,
    >   transform(journey_statuses) using 'python abbreviateList.py' as journey_statuses_abbreviated
    > from journeys;
NoViableAltException( ... wall of Java error messages ... )
FAILED: ParseException line 3:2 cannot recognize input near 'transform' '(' 'journey_statuses' in select expression

, ?

+4
1

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TRANSFORM Hive?

Python, object_id , , .

+5

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