We've discussed in the dev list recently a strong distaste for the "collection" param. Is the issue you speak of equivalent if the collection is instead in the natural place in the path is comma-delimited?
On Thu, May 7, 2026 at 3:33 AM Mikhail Khludnev <[email protected]> wrote: > Devs, > After looking into it, I've got a two chairs question, either: > > - manage RTG /get to handle `collection` > < > https://github.com/apache/solr/blob/main/solr/core/src/java/org/apache/solr/handler/component/RealTimeGetComponent.java#L1046 > > > param, > or > - let {!mlt} ignore no doc found error > < > https://github.com/apache/solr/blob/a2370b58380e61633e0e1b65312bb33201eea3cd/solr/core/src/java/org/apache/solr/search/mlt/CloudMLTQParser.java#L53 > > > in case if the `collection` param is sent, assuming the will be found in > another collection > > The latter approach causes a slight negative regression: it won't throw an > error in case of the nonexistent ID anymore. > So, which one do you choose? > . > > On Wed, May 6, 2026 at 8:49 PM Mikhail Khludnev <[email protected]> wrote: > > > Hi there. > > Here we got https://github.com/mkhludnev/solr/pull/1 it's a rough cut. > > How you feel about it? > > > > On Wed, May 6, 2026 at 8:06 PM Mikhail Khludnev <[email protected]> wrote: > > > >> Hi > >> It looks like > >> > https://github.com/apache/solr/blob/main/solr/core/src/java/org/apache/solr/search/mlt/CloudMLTQParser.java#L101 > >> is not clusteraware at all. > >> It lacks functionality, needs to be developed. > >> > >> On Wed, May 6, 2026 at 7:47 PM Till Kinstler <[email protected]> wrote: > >> > >>> Hi all, > >>> > >>> we have a use case, where we would like to make a MoreLikeThis Query > >>> Parser request across two collections (of multiple shards each) in a > >>> SolrCloud. The two collections share the same index schema. > >>> The request looks like > >>> q={!mlt qf=field1,field2}ID&collection=collection1,collection2 > >>> > >>> It results in an error message "Error completing MLT request. Could not > >>> fetch document with id [ID]" from one of the shards of the collection > >>> not containing the document with id ID. > >>> > >>> So I guess, while the MoreLikeThis Query Parser is "SolrCloud aware" > and > >>> can handle MLT requests across multiple shards of one collection (works > >>> fpr us), it can not deal with multiple collections? Or are we missing > >>> something? Is there a way to send one MoreLikeThis Query Parser request > >>> to multiple SolrCloud collections? > >>> > >>> Thanks for any help, > >>> Till > >>> > >>> -- > >>> Till Kinstler > >>> Verbundzentrale des Gemeinsamen Bibliotheksverbundes (VZG) > >>> Platz der Göttinger Sieben 1, D 37073 Göttingen > >>> [email protected], http://www.gbv.de/ > >>> > >>> > >> > >> -- > >> Sincerely yours > >> Mikhail Khludnev > >> > > > > > > -- > > Sincerely yours > > Mikhail Khludnev > > > > > -- > Sincerely yours > Mikhail Khludnev >
