You could use the UUIDUpdateProcessorFactory to automatically add a UUID to each document and use that as the tie-breaker field.
https://solr.apache.org/guide/8_1/update-request-processors.html#uuidupdateprocessorfactory The chances of collision of UUIDs is well-known, and highly unlikely. https://en.wikipedia.org/wiki/Universally_unique_identifier#Collisions > On 31 Aug 2021, at 14:04, rgamarra <rgama...@gmail.com> wrote: > > hi, > >> Random ≠ unique. > > Agree. They are not the same. I don't want a tie breaker, I want to know > how many ties I would face. > > The implementation where it's being used has some other (posterior) sorting > criteria. So the question can be rephrased as whether posterior orders have > any effect or not. > > For example, given > > sort= random_1234 DESC, price DESC > > At the end of the day, does the "price DESC" have any effect (which > translates to how often ties in the random do happen)? > > I took a glimpse at > https://github.com/apache/solr/blob/main/solr/core/src/java/org/apache/solr/schema/RandomSortField.java > and I conclude that > - an int is being used. > - it's a hashing of the #doc + see, more than a random number generator of > a certain distribution. > > Best. Thanks. > > > -- > Rodolfo Federico Gamarra > > > On Tue, Aug 31, 2021 at 3:00 AM Thomas Corthals <tho...@klascement.net> > wrote: > >> Hi Rodolfo >> >> Random ≠ unique. If you really need a tie breaker, you'll have to sort on >> the uiqueKey field. >> >> What is your use case here? When using a cursor, sorting on a random field >> will yield confusing results. >> >> Thomas >> >> Op ma 30 aug. 2021 om 17:33 schreef rgamarra <rgama...@gmail.com>: >> >>> Hi there! I'm using random fields (eg sort=random_1234 DESC) as a tie >>> breaker. >>> >>> I'm wondering the underlying random sequence how many digits uses for >> each >>> generated number. >>> >>> My result sets my contain (in principle) millions of results, so I would >>> like to have an estimation of possible clashes (ie two results ending >> with >>> the same random under, and then being a tie in the result set). >>> >>> Best regards. >>> >>> -- >>> Rodolfo Federico Gamarra >>> >>
