Hi Anthony, I was waiting for a post like yours where we can understand better what is missing in OrientDB to provide the same level of reactiveness of RethinkDB.
I leave to @Luigi to comment this email point by point. However, even if the Live Query feature is a quite new feature in OrientDB, it's definitely one of the main things where we are focusing on. Thanks. Best Regards, Luca Garulli Founder & CEO OrientDB LTD <http://orientdb.com/> Want to share your opinion about OrientDB? Rate & review us at Gartner's Software Review <https://www.gartner.com/reviews/survey/home> On 11 October 2016 at 16:03, Anthony <[email protected]> wrote: > Now that RethinkDB is shutting down, I have been looking at OrientDB, > particularly its LiveQuery feature. I am interested in the extent to which > LiveQuery is comparable to RethinkDB Changefeeds. In particular: > > - Are there any limitations on the types of queries with which > LiveQuery works? Can you put "LIVE" in front of any "SELECT" command and > get a working LiveQuery? > - More specifically, does LiveQuery work on queries involving links? > For example, suppose you have a query that retrieves a set of blog posts > and their linked comments -- does the LiveQuery send a change notification > when a linked comment is inserted/updated/deleted in the LINKLIST? > - In RethinkDB, changefeeds involving orderby and limit can be > configured to send the old and new offset of each change (via the > include_offsets option) so you can easily insert the change into the proper > place within the previously returned set of records. Is this possible with > LiveQuery, or do you have to manage the ordering manually on the client? > - If you want the initial set of records followed by any subsequent > changes, do you have to issue an initial SELECT followed by a LIVE SELECT? > If so, is there any way to ensure you don't miss any changes between the > two (RethinkDB achieves this with its include_initial option). > - Can OrientDB do filtering on the changes themselves? For example, in > RethinkDB, you can do: > > > r.table('test').changes().filter{ |row| > row['new_val']['score'] > row['old_val']['score'] > } > > The above changefeed will only return changes where the new score is > greater than the old score. Is this possible with live queries? > > - Does LiveQuery have anything similar to the RethinkDB "squash" > option, which can be set to squash a set of changes that happen within a > particular timespan into just a single change? > - How scalable are live queries? If you have a web application with > tens or hundreds of thousands of connected users, each user with several of > their own unique live queries, will OrientDB be able to handle that. The > RethinkDB Horizon docs claim it is "designed to support millions of > realtime feeds" (with proper horizontal scaling of the database). Is > OrientDB in the same league? What kind of load would be realistic for a > single server, and is there any bottleneck that would inhibit horizontal > scaling to support more and more live queries? > - Any other notable differences from RethinkDB changefeeds? > > More generally, what is OrientDB's commitment to developing and promoting > the LiveQuery feature? RethinkDB promotes its changefeeds as its primary > distinguishing feature ("The open-source database for the realtime web"). > However, it does not appear that LiveQuery is mentioned *anywhere *on the > marketing parts of the OrientDB website (except for a single year-old blog > post), and you have to dig fairly deep in the documentation to discover the > feature even exists. Is this feature a priority for OrientDB? > > Finally, given RethinkDB's recent fate, it would be nice to know more > about the health of OrientDB LTD. Is the company profitable and poised to > be around for a while? > > Thank you. > > Anthony > > -- > > --- > You received this message because you are subscribed to the Google Groups > "OrientDB" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- --- You received this message because you are subscribed to the Google Groups "OrientDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
