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Hive >> mail # user >> unexplode?

Also I have a colllect udf.

Since collect sets removes duplicates.

On Thu, Aug 23, 2012 at 1:26 PM, Philip Tromans
> insert into originalTable
> select uniqueId, collect_set(whatever) from explodedTable group by uniqueId
> will probably do the trick.
> Phil.
> On 23 August 2012 17:45, Mike Fleming <[EMAIL PROTECTED]> wrote:
>> I see that hive has away to take a table and produce multiple rows.
>> Is there a built in way to do the reverse?
>> Say I have a table with a unique key and an array. I do this:
>>> insert into explodedTable select uniqueId, explode(arrayOfThings) from
>>> originalTable
>> Now I have a table with a row for each (uniqueId, element in arrayOfThings).
>> Is there any way to take the contents of explodedTable and essentially
>> produce the original table, reconstructing the arrayOfThings for each
>> uniqueId?
>> It seems, conceptually, that if I "cluster by uniqueId" then a reducer knows
>> that it will get all rows for each uniqueId bundled together, so it ought to
>> be fairly feasible to simply emit an unexploded row. However, I can't seem
>> to find a built-in way to do this.
>> Mike