It seems cursorMark is not supported in CSV format, and it could be developed after discussing a particular format. Another approach is to develop a result transformer, which prints cursor mark at every CSV row as a field value, I'm not 100% sure it may work.
Btw, couldn't you just export docs to json lines via https://solr.apache.org/guide/solr/latest/deployment-guide/solr-control-script-reference.html#exporting-documents-to-a-file and then transform it to csv. It should be easy, ha? On Tue, Jun 10, 2025 at 12:01 PM James Baster < james.bas...@opendataservices.coop> wrote: > Hello Rahul, > > If I do that all I get back is the CSV. There is no "nextCursorMark" data > available. If I want to get the "nextCursorMark" data I seem to have to use > JSON output. This makes it impossible to combine the 2 features and get > more than 1 page of information. > > (I did think of a slightly better workaround right after posting, but am > curious if there is any way to combine these 2 features I've just missed?) > > Thanks, > James > > > > On Wed, 4 Jun 2025 at 17:41, Rahul Goswami <rahul196...@gmail.com> wrote: > > > Can you please explain why the 2 calls? Are you not able to get the > result > > the first time with wt=csv and cursorMark=* ? > > > > Rahul > > > > > > On Wed, Jun 4, 2025 at 10:45 AM James Baster < > > james.bas...@opendataservices.coop> wrote: > > > > > I know that when paging through a big set of results, using cursorMark > is > > > better than using start/rows pagination because cursorMark works better > > > when data may be inserted/updated/deleted during pagination and it can > > have > > > better performance. > > > > > > > > > https://solr.apache.org/guide/solr/latest/query-guide/pagination-of-results.html > > > > > > I know that there are Response Writers, so that if I want to get my > > results > > > in CSV I can, just by changing the wt parameter. > > > > > > https://solr.apache.org/guide/solr/latest/query-guide/response-writers.html > > > > > > So my question is, what if I want to combine them? Get a bunch of CSV's > > > nicely paginated with cursorMark? > > > > > > I can't see any options to do this - are there any? > > > > > > Are there any good workarounds? > > > > > > I could just page with start/row and accept the problems with that. > > However > > > if a row is inserted/deleted/moved above my current position, my data > > will > > > shift by 1 and that's not great. > > > > > > I could use cursorMark with 2 queries per page, like: > > > > > > * set cursorMark to last known cursorMark or "*" if it's the start. > > > * call API once with JSON response writer. Note the value of > > > nextCursorMark. > > > * call API a second time with CSV response writer. Save my CSV result > > > somewhere. > > > * maybe pause a second to avoid rate limiting. > > > * If nextCursorMark is different from last cursorMark there are more > > > results so loop over again. > > > > > > With this system, if a row is inserted/deleted/moved above my current > > > position, my data will not shift - great. However if a row is > > > inserted/deleted/moved in my current page between the 2 queries, I may > > miss > > > a row or double count a row. > > > > > > Any better options? > > > > > > Thank you in advance, > > > James > > > > > > -- Sincerely yours Mikhail Khludnev
