Hi All,
    My company has a inhouse db like elasticsearch but only index based search, no columnar.
I see that janusgraph mostly has columnar db as the primary data storage.
1. can we plugin our own db, is it allowed?
2. why only columnar as the primary db, any reasons.
   index based lucene also can support like getting all the indexed documents.
any reason why columnar as the primary backend?
thanks,
Kalpa