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
