evnc
Joined 5 years ago
Joined 5 years ago
I wonder if there's a place for such architecture in the operational path, not just analytics. If you squint, "this microservice reads data from this operational DB and passes it to this other microservice / puts it in a cache / sends it in response to a request" looks sort of like an "ad hoc, informally specified, bug-ridden, slow"[0] implementation of incremental view maintenance (in that a cache, or a service's data model in memory, is a sort of "materialized view" over the source data). I've seen some success in replacing a tangle of imperative-languages-and-network-requests with a declarative, incrementally maintained model in SQL, if the read latency can be kept under control.
I'm curious about the "some amount of streaming influence moving back into the batch systems, particularly as object storage gives us the ability to run stateful workloads with less operational headache" part. could you expand on that?
[and yes, I do find these sort of problems interesting! :)]
SELECT 'black' AS outline_color
FROM elements parent
JOIN elements child ON parent.id = child.parent_id
WHERE parent.data_theme = 'light'
AND child.data_theme = 'dark'
AND child.focused = true
there's a lot of ways to express the same thing! it's interesting to notice the connections between them, I think, and their strengths and weaknesses, e.g. I probably wouldn't want to write my whole design system in SQL, but since it's relational queries over the elements structure and properties, you could.eg this example:
[data-theme="dark"] [data-theme="light"] :focus {
outline-color: black;
}
means, in English/pseudocode, roughly: "If you have an element X with attribute data-theme="dark", and X has a child Y with attribute data-theme="light", and Y is focused, then the outline-color of Y is black".so we could write this also as, e.g.:
outline-color(Y, black) if
data-theme(X, "dark") and
parent(X, Y) and
data-theme(Y, "light") and
focused(Y)
that's Datalog, except I went ahead and replaced :- with "if" and "," with "and".if we want even more syntax sugar, we could do:
Y.outline_color := black if
X.data-theme == dark and
Y.parent == X and
Y.data-theme == dark and
Y.focused
imagine `X.attr == val` <==> `attr(X, val)` as a kind of UFCS for Datalog to make it palatable to Regular Programmers, rightthe declaration and scope of these variables is implicit here; if you want something even more ALGOL-family, we could write
forall Y {
Y.outline_color := black if
Y.data_theme == "dark" and
Y.focused and
Y.parent.data_theme == "light"
}
here we've explicitly introduced Y, and made one of our joins implicit, and it looks even more like Regular Programming now, except the Datalog engine (or equivalent) is kind of running all these loops for you, every time one of their dependencies changes, in an efficient way ...> we copy and reapply patterns in different contexts and that might enable unexpected things
yeah, that's exactly what I am trying to do here. Mostly it doesn't go anywhere, but it's interesting for the hacker spirit within me :)
I think the conclusion (which I may not have made clear enough) is less like "These are limitations of modern CSS which ought to be fixed" and more "Maybe a CSS-like syntax could be added to a Datalog-like system and that would be helpful for making it more accessible to more engineers, navigating tree-shaped data, etc"
thanks for the feedback, anyway!
What would your ideal RDBMS / tooling look like, that facilitates 6nf effectively? Do you think it's more a limitation of the query/storage engine, or the query language (SQL), or the user interface? Do you think founding on Datalog (or similar), which kinda lends itself to "narrow" relations, instead of SQL which kinda lends itself to "wide" relations, would help here?
(I ask as one of my personal hobby-horses is trying to design better query languages and tooling, and 6nf/datalog maintains a kinda special place in my heart)