Philip Tromans 2012-08-23, 17:26
insert into originalTable
select uniqueId, collect_set(whatever) from explodedTable group by uniqueId
will probably do the trick.
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
> 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
> 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.