Thanks Doug. The previous discussion suggests that-> Hypertable provides row level transactions. (i.e. the consistency is provided at the level of a row --correct me if I am wrong) Here, what does a row mean? The complete row corresponding to a single key i.e. all the columns and all the revisions (like BigTable) or a key and one particular version(timestamp).
On Feb 2, 8:17 pm, Doug Judd <[email protected]> wrote: > Hi Harshada, > > Hypertable currently doesn't support ACID transactions. We've carefully > designed the system so that it could support transactions in the future. > All updates go into a commit log in the DFS for durability. Each cell has a > 64-bit revision number associated with it. We use this revision number for > snapshot isolation, to support Multi-version concurrency control (MVCC). > It's possible for the revision number to be supplied with inserts and > queries. We envision some day building a transaction monitor that sits in > front of a Hypertable cluster to provide distributed transactions. > > It's also fairly simple to provide row-level transactions. All of the data > for a given row resides in the same range. This allows us to easily build > row-level transaction mechanism. On our near term roadmap, we plan to add > support for integer counters and an atomic increment operation, which is > essentially a specialized transaction. We may build that on top of a more > generalized row-level read-modify-write mechanism as described in the > Bigtable paper. > > Is there a specific transaction use case that you would like to see > supported? > > - Doug > > On Mon, Feb 1, 2010 at 9:20 PM, Harshada <[email protected]> wrote: > > Hi, > > > I am new to this field. So, please pardon me if my questions are too > > naive. > > >http://groups.google.com/group/hypertable-user/browse_thread/thread/a... > > > tells us that Hypertable supports simple row/range level transactions. > > > My questions are: > > > 1. Is it like the traditional transaction support- i.e. including > > locking, logging, recovery etc? If yes, where can I find related files > > in the source? > > 2. Is it similar/on the parallel lines of BigTable's tablet level > > transaction support? > > > Thanks, > > > Harshada > > > -- > > You received this message because you are subscribed to the Google Groups > > "Hypertable Development" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]<hypertable-dev%[email protected]> > > . > > For more options, visit this group at > >http://groups.google.com/group/hypertable-dev?hl=en. -- You received this message because you are subscribed to the Google Groups "Hypertable Development" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/hypertable-dev?hl=en.
