Topic on Talk:Quarry

I am learning how to use Quarry to query Wikidata data. I have written these two queries:

1. Get the number of statements on a Wikidata item given its QID
2. Get all revisions on a Wikidata item given its QID

I now want to write a SQL query that gets the current statements on a Wikidata item given its QID (the returned rows should be the same of those rows returned by this SPARQL query). This is my initial idea on how to do it: I know that the table revision contains all the revisions on a given page and the table comment contain information on the introduced changes, so one way to do what I want to do is to parse the column comment_text (see an example in the results of query 2 above), which describes the changes, and determine the latest changes. I think this method is complex to implement using SQL since I need to determine which changes were not edited by any other other changes. I wonder if there's a simpler approach or a table that already contains the current statements on a Wikidata item.

I know that the current statements on a Wikidata item can be easily obtained in SPARQL (this query already does that), but since I'm learning how to query data in Quarry (i.e. using SQL), reading a SQL query that does that would help me to understand more about how data is stored and should be queried in Quarry.

I wonder if there's a simpler approach or a table that already contains this information. SQL queries are not suitable for Wikidata data model, that's why Wikidata Query Service exists. Some SQL queries are possible, but they are rather management-oriented, not data-oriented.

For the record, I asked a similar question in Libera Chat's room #wikimedia-cloud and some user replied the following:

18:50 <rdrg109> For the record, I have created a topic with that question in Talk:Quarry here: https://www.mediawiki.org/wiki/Topic:Y3u6dz3ci6eqlura
19:08 <+wm-bb> <<hidden user>> rdrg109: it’s basically not doable. it’s best to use SPARQL instead
19:30 <rdrg109> <<hidden user>>: Ok, thanks for the help!

More of the IRC discussion around this topic can be seen in the chat log at https://wm-bot.wmcloud.org/browser/index.php?start=04/29/2024&end=04/29/2024&display=%23wikimedia-cloud

It is impossible to reconstruct all claims from comment_text. There are several Wikibase API commands that create or edit entities without specifying in the comment text which claims are created, removed or modified. See for example the creation of d:Q125692383 today which was created with 5 claims at once without it being visible in the comment.