frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Open in hackernews

Anatomy of a SQL Engine

https://www.dolthub.com/blog/2025-04-25-sql-engine-anatomy/
168•ingve•11mo ago

Comments

jimbokun•11mo ago
Very nice write up enumerating all the stages of SQL query execution. Interesting even if you don’t care about the DoIt database specifically.
Austizzle•11mo ago
Man, this title tripped me up for a minute because I pronounce it with the letters like Ess-Queue-Ell

So the "A" in "A ess-queue-ell" engine felt like it should have been an "An" until I realized it was meant to be pronounced like "sequel"

perching_aix•11mo ago
Not necessarily, I see native speakers completely ignore this a lot.

Have you ever considered pronouncing it as squirrel by the way?

kreetx•11mo ago
Many (most?) non-native English speakers do pronounce it as ess-queue-ell, especially in their own languages, so yes, the use of "a" instead of "an" does look off from that perspective.
SloopJon•11mo ago
When I read SQL for Dummies almost thirty years ago, it made a point of distinguishing "sequel" as a historical predecessor to standard "SQL." As I recall, the author even asserted that SQL is not an acronym/initialism for structured query language. I felt funny saying sequel for the next decade or so, because I wasn't an old timer experienced with this pre-SQL technology.

Now I usually say sequel because everyone else does. That and it rolls off the tongue better than S-Q-L.

jtolmar•11mo ago
I prefer "ess queue ell" these days, but the first DBA I ever worked with pronounced it "squirrel".
gopalv•11mo ago
This is a great write up about a pull-style volcano SQL engine.

The IR I've used is the Calcite implementation, this looks very concept adjacent enough that it makes sense on the first read.

> tmp2/test-branch> explain plan select count() from xy join uv on x = u;

One of the helpful things we did was to build a graphviz dot export for the explains plans, which saved us days and years of work when trying to explain an optimization problem between the physical and logical layers.

My version would end up displayed as SVG like this

https://web.archive.org/web/20190724161156/http://people.apa...

But the calcite logical plans also have that dot export modes.

https://issues.apache.org/jira/browse/CALCITE-4197

th0ma5•11mo ago
This is really great!!
gavinray•11mo ago
Calcite also has a relatively-unknown web tool for plan visualization that lets you step through execution.

It's a method from "RuleMatchVisualizer":

https://github.com/apache/calcite/blob/36f6dddd894b8b79edeb5...

Here's a screenshot of what the webpage looks like, for anyone curious:

https://github.com/GavinRay97/GraphQLCalcite/blob/92b18a850d...

ignoreusernames•11mo ago
I recommend anyone who works with databases to write a simple engine. It's a lot simpler than you may think and it's a great exercise. If using python, sqlglot (https://github.com/tobymao/sqlglot) let's you skip all the parsing and it even does some simple optimizations. From the parsed query tree it's pretty straightforward to build a logical plan and execute that. You can even use python's builtin ast module to convert sql expressions into python ones (so no need for a custom interpreter!)
Abde-Notte•11mo ago
Second this - building even a simple engine gives real insight into query planning and execution. Once parsing is handled, the core ideas are a lot more approachable than they seem.
albert_e•11mo ago
Sorry for slight digression.

In a larger system we are building we need a text-to-sql capability for some structured data retrieval.

Is there a way one could utilize this library (sqlglot) to build a multi-dialect sql generator -- that is not currently solved by directly relying on a LLM that is better at code generation in general?

LtdJorge•11mo ago
This is a SQL to X library, though. I don’t think it’s what you need.
gavinray•11mo ago
You can use an LLM to generate query-builder expressions from popular libraries in whatever language.

For example, on the JVM there is jOOQ, which allows you to write something like:

  select(field("foo"), avg("bar")).from(table("todos"))
And then it will render dialect-specific SQL. It has very advanced emulation functionality for things like JSON aggregations and working around quirks of dialects.

Alternatively, you can ask an LLM to generate a specific dialect of SQL, and then use jOOQ to parse it to an AST, and then render it as a different dialect, like:

    val parser= DSL.using(SQLDialect.POSTGRES).parser()
    val parsedQuery = parser.parseQuery(postgresQuery)
    val renderedMySQL = DSL.using(SQLDialect.MYSQL).renderInlined(parsedQuery)
    println(renderedMySQL)
Unsure if functionality like this exists in other Query Builder libraries for other languages.
genai-analyst•10mo ago
another digression here... sorry... i see you're trying to diy text-to-sql—at some point you're gonna hit a bunch of hiccups. like, the model writes a query that “almost” works but joins the wrong tables, or it assumes column names that don’t exist, or it returns the wrong agg because it misread the intent. and retries won’t always save you—it’ll just confidently hallucinate again.

we’ve been through all of that at wobby.ai we ended up building a system where the data team defines guardrails and reusable query templates, so the agent doesn’t just make stuff up. it can still handle user prompts, but within a safe structure. if you want to save yourself from debugging this stuff endlessly, might be worth checking out wobby.ai.

KyleBrandt•11mo ago
Using dolthub's go-mysql-server for Grafana's upcoming SQL expressions feature (private preview in Grafana 12, but in the OSS version with a feature toggle).

GMS lets you provide your own table and database implementations, so we use GMS to perform SQL queries against Grafana's dataframes - so users can join or manipulate different data source queires, but we don't have to insert the data into SQL to do this thanks to GMS.

My Astrophotography in the Movie Project Hail Mary

https://rpastro.square.site/s/stories/phm
393•wallflower•3d ago•123 comments

Local LLM App by Ente

https://ente.com/blog/ensu/
263•matthiaswh•5h ago•114 comments

Thoughts on Slowing the Fuck Down

https://mariozechner.at/posts/2026-03-25-thoughts-on-slowing-the-fuck-down/
201•jdkoeck•3h ago•135 comments

Jury says Meta knowingly harmed children for profit, awarding landmark verdict

https://www.latimes.com/business/story/2026-03-25/jury-says-meta-knowingly-harmed-children-for-pr...
142•1vuio0pswjnm7•1h ago•17 comments

Meta and YouTube Found Negligent in Landmark Social Media Addiction Case

https://www.nytimes.com/2026/03/25/technology/social-media-trial-verdict.html
50•mrjaeger•36m ago•8 comments

TurboQuant: Redefining AI efficiency with extreme compression

https://research.google/blog/turboquant-redefining-ai-efficiency-with-extreme-compression/
401•ray__•13h ago•114 comments

Antimatter has been transported for the first time

https://www.nature.com/articles/d41586-026-00950-w
171•leephillips•3h ago•84 comments

Show HN: I built a site that maps the web from a bounty hunter's perspective

https://www.neobotnet.com/
20•caffeinedoom•1d ago•0 comments

Goodbye to Sora

https://twitter.com/soraofficialapp/status/2036532795984715896
985•mikeocool•22h ago•734 comments

VitruvianOS – Desktop Linux Inspired by the BeOS

https://v-os.dev
279•felixding•14h ago•180 comments

Looking at Unity made me understand the point of C++ coroutines

https://mropert.github.io/2026/03/20/unity_cpp_coroutines/
112•ingve•3d ago•99 comments

Sony V. Cox Decision Reversed

https://supreme.justia.com/cases/federal/us/607/24-171/
70•rileymichael•2h ago•43 comments

Flighty Airports

https://flighty.com/airports
468•skogstokig•17h ago•162 comments

Building a coding agent in Swift from scratch

https://github.com/ivan-magda/swift-claude-code
45•vanyaland•7h ago•12 comments

Tell HN: Litellm 1.82.7 and 1.82.8 on PyPI are compromised

https://github.com/BerriAI/litellm/issues/24512
864•dot_treo•1d ago•462 comments

Show HN: I took back Video.js after 16 years and we rewrote it to be 88% smaller

https://videojs.org/blog/videojs-v10-beta-hello-world-again
560•Heff•1d ago•115 comments

Musketeer d'Artagnan's remains believed found under Dutch church

https://www.bbc.co.uk/news/articles/cm2rew2dgzzo
46•xenocratus•2h ago•13 comments

Slovenian officials blame Israeli firm Black Cube for trying to manipulate vote

https://www.wsj.com/world/europe/spies-lies-and-fake-investors-in-disguise-how-plotters-tried-to-...
315•cramsession•1h ago•126 comments

Miscellanea: The War in Iran

https://acoup.blog/2026/03/25/miscellanea-the-war-in-iran/
213•decimalenough•13h ago•284 comments

Meta and Google found liable in social media addiction trial

https://www.bbc.co.uk/news/articles/c747x7gz249o
9•ColinWright•23m ago•1 comments

Data centers are transitioning from AC to DC

https://spectrum.ieee.org/data-center-dc
240•jnord•17h ago•300 comments

VNDB founder Yorhel has died

https://vndb.org/t24787
155•indrora•3d ago•24 comments

Quantization from the Ground Up

https://ngrok.com/blog/quantization
35•samwho•1h ago•8 comments

Apple Business

https://www.apple.com/newsroom/2026/03/introducing-apple-business-a-new-all-in-one-platform-for-b...
702•soheilpro•1d ago•393 comments

Tracy Kidder, Author of 'The Soul of a New Machine,' Dies at 80

https://www.nytimes.com/2026/03/25/books/tracy-kidder-dead.html
21•ghc•1h ago•4 comments

Supreme Court Sides with Cox in Copyright Fight over Pirated Music

https://www.nytimes.com/2026/03/25/us/politics/supreme-court-cox-music-copyright.html
135•oj2828•3h ago•82 comments

I wanted to build vertical SaaS for pest control, so I took a technician job

https://www.onhand.pro/p/i-wanted-to-build-vertical-saas-for-pest-control-i-took-a-technician-job...
395•tezclarke•20h ago•171 comments

Hubble Snaps a New Dazzling Photo of the Crab Nebula

https://nautil.us/hubble-snaps-a-new-dazzling-photo-of-the-crab-nebula-1279203
39•Brajeshwar•2h ago•5 comments

Arm AGI CPU

https://newsroom.arm.com/blog/introducing-arm-agi-cpu
395•RealityVoid•1d ago•288 comments

Microbenchmarking Chipsets for Giggles

https://chipsandcheese.com/p/microbenchmarking-chipsets-for-giggles
42•zdw•2d ago•2 comments