Datalog equivalent of simple query: `{{query [[ML]]}}`

Questions & Help Queries
1

I’m trying to understand advanced queries. So I thought I’d start with something simple. What’s the equivalent of

{{query [[ML]]}}

Also, I wanted to see how to create a query that would not print the “Live query” comment and Query builder UI. So the #+BEGIN_QUERY and #+END_QUERY syntax seems to do that. But it didn’t work with the simple query.

I asked GPT-4, but its several attempts didn’t return any results. The simple one above does.

Questions:

  1. What does this actually do? It appears to return the page named “ML” and pages that reference it, whether with “#ML” or “[[ML]]”. Great.

  2. Is there a way to see the Datalog source for the simple query?

  3. Back to the main question: How to write the equivalent of {{query [[ML]]}} in the advanced syntax?

Thanks!

2

You might want to check Using dynamic variables in queries - #2 by FlorianF and a plethora of other posts scattered accross this forum, like Is there any documentation on Simple Queries inside Advanced Queries? for example.

1 Like
3

Welcome. Should read the documentation and the Additional Links. For your specific question, check Example 1 - Find a Tag

1 Like
4

Thanks @FlorianF and @mentaloid for those links. I find that inserting the simple query into an advanced query, per this link works as expected:

#+BEGIN_QUERY
{ :title "ML"
  :query [[ML]] 
  :collapsed? false
}
#+END_QUERY

It returns a link to the ML page and a list of references that mention it.

This is great as it answers one of my questions above: How to write a simple query but not show the “Live query” annotation and Query Builder UI.

However, the full advanced query from Example 1 - Find a Tag, does not work.

#+BEGIN_QUERY
{ :title "Find tag: ML"
  :query [
    :find (pull ?b [*])
    :where
      [?b :block/ref-pages ?p]
      [?p :block/name "ML"]
  ]
}
#+END_QUERY

It returns “No matched result”. Is the example incorrect? Has something changed?

5

Yes, it has changed. Check also the schema.

6

Success! The following returns both the ML page and the references to it, like {{query [[ML]]}}. Note that the matching text must be written in lowercase.

#+BEGIN_QUERY
{ :title "Find tag: ML"
  :query [
      :find (pull ?b [*])
      :where
        (or (and [?b :block/refs ?p] [?p :block/name "ml"])
            (and [?b :block/page ?p] [?p :page/name "ml"])
        )
  ]
}
#+END_QUERY

If there’s a more concise way to write it, please let me know.

7

Could be shortened like this:

#+BEGIN_QUERY
{ :title "Find tag: ML"
  :query [
      :find (pull ?b [*])
      :where
        [?p :block/name "ml"]
        (or [?b :block/refs ?p]
            [?b :block/page ?p]
        )
  ]
}
#+END_QUERY
8

Ah, I see it! Thanks!