Different vertex Ids with exactly same properties
I am using Janusgraph 1.0.0-rc2 with Cassandra as a backend.
I recently encountered an issue where I saw two different vertices with different vertex ID but have exactly same properties,
Even when I have indexed the property as UNIQUE.
Is this a known issue of rc2 version?
5 Replies
So, I noticed that I have set read-consistency-level as ONE and write-consistency-level as QUORUM,
I doubt this can give opportunity for race condition, where some cassandra nodes has yet to be completed the write operation for a particular record but another service pod has read for the same record ID and thinks that the record does not exist.
Did you also manually set the consistency to
LOCK as described here? https://docs.janusgraph.org/advanced-topics/eventual-consistency/#data-consistency
That section also contains a warning about using unqiueness constraints with evantual consistent backends like CassandraThanks for the response @florianhockmann
No, I have not set it yet.
I have to say though that I don't have much experience with the built-in locking mechanism of JanusGraph as we have implemented our own locking mechanism outside of JanusGraph at my company since it didn't suffice for our needs. If you're interested in this, I wrote a blog post about our approach a few years back: https://www.gdatasoftware.com/blog/2018/12/31280-how-to-avoid-doppelgangers-in-a-graph-database
Thanks Florian, that will be really helpful.