Phoenix is a relatively recent project that represents a SQL layer over HBase. Its blog is at http://phoenix-hbase.blogspot.com/, and it was first announced at this blog on January 30, 2013.
Here is a brief list of only some of the capabilities that it gives you:
TABLE)to add/remove columns
VALUESfor row-by-row insertion,
SELECTfor mass data transfer between the same or different tables, and
DELETEfor deleting rows
Most importantly, it does not provide ...