Lance Norskog [goks...@gmail.com] wrote: > It would be handy to have an auto-incrementing date field, so that > each document would get a unique number and the timestamp would then > be the unique ID of the document.
If someone want to implement this, I'll just note that the granilarity of Solr dates is fixed to milliseconds: http://lucene.apache.org/solr/api/org/apache/solr/schema/DateField.html Using ms for unique timestamps means limiting the index rate to 1000 documents/second. That might be okay for some applications but a serious limiter for other (our Lucene index update rate varies between 300 and 1600 documents/second, depending on content, I am sure others have much higher rates). One could do tricks, but it is just plain ugly to use something like "Tenths of milliseconds since epoch", so switching to longs and nanoseconds seems to be the clean choice if we want the timestamps to be "true" timestamps and not just a unique integer-ID generator.
