We now try to perform writes in a reasonably sane order, but only
update one record at a time (or do a batch against the same table
but not in a transaction).
This matches with eventually consistent databases like Cassandra
where we can't rely upon a transaction being available for any
sort of update we make.
Change-Id: Ib8cdff05f08467dfe3258f03b72d5cabb5b2641f
Signed-off-by: Shawn O. Pearce <sop@google.com>
113860696a