Thanks Tyler. So have you actually tried this with Cassandra?
On Apr 24, 2012, at 5:44 AM, Tyler Hobbs wrote: > At least for TimeUUIDs, this email I sent to client-dev@ a couple of weeks > ago should help to explain things: > http://www.mail-archive.com/client-dev@cassandra.apache.org/msg00125.html > > Looking at the linked pycassa code might be the most useful thing. > > On Tue, Apr 24, 2012 at 1:46 AM, Drew Kutcharian <d...@venarc.com> wrote: > Hi All, > > Considering that UUIDs are compared as numbers in Java [1], what are the > lowest and highest possible values a valid UUID can have? How about TimeUUIDs? > > The reason I ask is that I would like to pick a "default" UUID value in a > composite column definition like Composite(UUID1, UUID2) where UUID1 can be > set to the default value if not supplied. In addition, it'd be nice if the > "default" columns are always sorted before the rest of the columns. > > I was thinking of just doing "new UUID(Long.MAX_VALUE, Long.MAX_VALUE)" or > "new UUID(Long.MIN_VALUE, Long.MIN_VALUE)" but not sure if that's going to > cause other issues that I'm not aware of. > > Thanks, > > Drew > > > [1] Here's the compareTo of java.util.UUID as a reference: > > public int compareTo(UUID val) { > // The ordering is intentionally set up so that the UUIDs > // can simply be numerically compared as two numbers > return (this.mostSigBits < val.mostSigBits ? -1 : > (this.mostSigBits > val.mostSigBits ? 1 : > (this.leastSigBits < val.leastSigBits ? -1 : > (this.leastSigBits > val.leastSigBits ? 1 : > 0)))); > } > > > > > -- > Tyler Hobbs > DataStax >
