Talk:To QLever

to_qlever and another query rewriter tool

@Kristbaum There was a question about this tool and a new one that I am creating on GitLab.

The question and my answer are on the Blazegraph Migration Office Hours etherpad (#7 on 4 Aug 2026) at https://etherpad.wikimedia.org/p/Blazegraph_Migration_Office_Hours.

I would appreciate any feedback that you have on my comments and on the revised tool. I have used your tool for inspiration - especially for the named subquery rewrites - and very much appreciate the work that you did!AWesterinen-WMF (talk) 18:37, 4 August 2026 (UTC)

Hi! I looked briefly at the code of your tool, and could already tell, that it is way more extensive and proper. To be honest, most of the changes To_QLever makes, are hacks I needed for specific Wikidata queries to work, and my analysis of the issues could be wrong.

On the topic of maximum number of language labels, this was just an observation, as the query I tried worked way better with fewer labels.

If there is interest I could collect some queries that showcase some of the issues To_Qlever tries to work around!

There are still a few cases where the translation is wrong still. Kristbaum (talk) 23:12, 6 August 2026 (UTC)

@Kristbaum Would love to see your use cases and add them to mine.

Right now, my "external" cases are examples from Wikidata and WMCloud. You can see the set on my GitHub page, https://github.com/AndreaWesterinen/Wikidata-Queries/tree/main/extract_sample_queries. All the "examples" and "xxx_examples" subdirectories are what I found online. AWesterinen-WMF (talk) 03:48, 7 August 2026 (UTC)

If you want a nearly complete list of the use cases, that were problematic, see the queries list at UsefulQueries (although some were later adapted to be less complex for QLever to begin with, but the old ones are still in the git history on the linked template).

There are still some lexeme based examples, that I'm struggling with, I may add them later this month, if that's of any interest to you. Kristbaum (talk) 09:28, 7 August 2026 (UTC)

Since lexemes are valid for querying, I could use more examples. I am interested! AWesterinen-WMF (talk) 16:21, 7 August 2026 (UTC)