boolean HTable.exists

From up on the list:

> From: Thibaut
> Subject: Exist function?
> To: hbase-user@hadoop.apache.org
> Date: Tuesday, December 30, 2008, 5:32 AM
>
> On a few occasions, I have to check if a key exists in a table or not.
>
> What's the best way to do it? The htable interface doesn't have any function to check if a key
> exists or not, and I have to specify at least one column when fetching a key.

It will be pretty easy to support an client side API addition in HRS. For memcache that would be containsKey() on the sorted maps. For disk, HStore could use getClosest() on the MapFile readers.

boolean testRow(final byte [] row);
boolean testRow(String row);