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Jim Ferenczi commented on LUCENE-7638: -------------------------------------- Thanks for taking a look @mattweber and [~mikemccand] {quote} Can this handle "side paths on side paths" graph structure (I think you called this "nested multi-term synonyms")? While no analysis chain can naturally produce this today (that I know of!), the TokenStream attributes can easily express it. And you could imagine it happening in the future, e.g. if you use Kuromoji tokenizer or WordDelimiterGraphFilter followed by a SynonymGraphFilter (except we'd need to e.g. use the synonym graph filter from LUCENE-5012, which can correctly consume a graph). If this is expected to work maybe we should add a test case showing that? {quote} I'll add a test case because it's expected to work ;) . This is also the reason why this patch does not produce {code}PhraseQuery{code} for synonyms. For simple "side paths" this is easy to do but we would need to switch to Span queries for "side paths on side paths" so I though that it could be done in another issue. {quote} It seems like you don't need to be using Term here, except at the end to pass to the newXXXQuery, since everything is in a single field here, and we are hoping to move away from Term entirely (LUCENE-7632)? {quote} Thanks, I'll simplify the patch. {quote} Holes are challenging for graph token streams ... can you add a test case that encounters holes, e.g. simulated StopFilter? There are at least two "fun" cases: a hole that cuts the graph entirely into two partitions, and a synonym spanning over a hole ... CannedTokenStream is useful for feeding such "interesting" cases. {quote} I though that holes would not be a problem for boolean queries but now I am not sure. I'll test that. {quote} The Path.id seems to be used only for tie-breaking on compare, not for lookup in the TreeSet as the comment suggests? {quote} The comment is misleading. It is needed because I use {code}TreeSet#remove{code} which uses compare to check object equality. So the {code}Path.id{code} is the unique identifier for the path. > Optimize graph query produced by QueryBuilder > --------------------------------------------- > > Key: LUCENE-7638 > URL: https://issues.apache.org/jira/browse/LUCENE-7638 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Jim Ferenczi > Attachments: LUCENE-7638.patch > > > The QueryBuilder creates a graph query when the underlying TokenStream > contains token with PositionLengthAttribute greater than 1. > These TokenStreams are in fact graphs (lattice to be more precise) where > synonyms can span on multiple terms. > Currently the graph query is built by visiting all the path of the graph > TokenStream. For instance if you have a synonym like "ny, new york" and you > search for "new york city", the query builder would produce two pathes: > "new york city", "ny city" > This can quickly explode when the number of multi terms synonyms increase. > The query "ny ny" for instance would produce 4 pathes and so on. > For boolean queries with should or must clauses it should be more efficient > to build a boolean query that merges all the intersections in the graph. So > instead of "new york city", "ny city" we could produce: > "+((+new +york) ny) +city" > The attached patch is a proposal to do that instead of the all path solution. > The patch transforms multi terms synonyms in graph query for each > intersection in the graph. This is not done in this patch but we could also > create a specialized query that gives equivalent scores to multi terms > synonyms like the SynonymQuery does for single term synonyms. > For phrase query this patch does not change the current behavior but we could > also use the new method to create optimized graph SpanQuery. > [~mattweber] I think this patch could optimize a lot of cases where multiple > muli-terms synonyms are present in a single request. Could you take a look ? -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org