Comment by cldellow | Hacker News Reader

Comment by cldellow | Hacker News Reader

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The simpler format is easier to generate, which can make the difference between having something and having nothing.

An example: our company uses redash for sharing ad hoc data sets internally. It'd be easy to generate a SQL expression with array_agg that could be wrapped in a span w/this font. I currently cruft up a call to a google charts replacement to do just that, which sucks because it adds a bunch of image requests.

I _could_ do it with SVG, too, but the expression to create it would be a lot more complex.

I can imagine submitting a PR to redash to autoformat any SQL column named "sparkline" with this font, actually.

(Valid criticism: maybe I should use a richer tool than redash for this...but I love it when a general tool can do a lot just because of composable primitives, AtF Spark fits the bill perfectly here.)

Good points, thank you. And take this as respectful musing not arguing...

> it would be a lot more complex

I don't use redash, but isn't the 'complexity' just the boiler plate literal text? The query is rather simple.

    '<svg ...etc... d="L' +
    SELECT ROW_NUMBER() OVER (ORDER BY Date DESC), Value FROM Data GROUP BY Date +
    '" ...etc... /></svg>'

No more complex than the google chart call, surely?

Yeah, "a lot more complex" is pretty sloppy. "A lot more annoying", perhaps. It's doable. The complexity comes when you aggregate tuples of (row number, value) instead of just aggregating value.

To fit in the redash model, you need a single expression that returns a string of HTML. So the example you cite isn't quite there, as I don't think it's valid SQL (or is it? I'm mainly familiar with Postgres--perhaps that example is valid in some other DB?)

So you need something like:

SELECT 'preamble' || (SELECT string_agg(ROW_NUMBER() OVER (ORDER BY Date Desc), ...) || 'postamble'

Except aggregate functions can't contain window functions, so something like:

WITH windowed as (SELECT ROW_NUMBER(), ...) SELECT 'preamble' || (SELECT string_agg(row_number || ',' value, ',') FROM windowed) || 'postamble'

is needed. Which isn't a big deal, but since you don't really care about the row number, it's nice to be able to skip the CTE and just directly smash the values into a string_agg.

It's a minor thing, but I'm lazy.

Hi! Arik from Redash here.

Mind sharing what you're doing today with me (the Google Charts approach)? My email is arik at redash.io.

Thanks!

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