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•11mo 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.

Artemis II crew take 'spectacular' image of Earth

https://www.bbc.com/news/articles/ce8jzr423p9o
356•andsoitis•3h ago•145 comments

iNaturalist

https://www.inaturalist.org/
293•bookofjoe•5h ago•89 comments

Show HN: TinyOS – A minimalist RTOS for Cortex-M written in C

https://github.com/cmc-labo/tinyos-rtos
28•hpscript•1h ago•8 comments

What changes when you turn a Linux box into a router

https://patrickmccanna.net/7-configuration-changes-that-turn-a-multi-homed-host-into-a-switch-rou...
65•0o_MrPatrick_o0•3d ago•14 comments

Show HN: I built a frontpage for personal blogs

https://text.blogosphere.app/
604•ramkarthikk•10h ago•166 comments

Oracle Files H-1B Visa Petitions Amid Mass Layoffs

https://nationaltoday.com/us/tx/austin/news/2026/04/03/oracle-files-thousands-of-h-1b-visa-petiti...
263•kklisura•2h ago•127 comments

Go on Embedded Systems and WebAssembly

https://tinygo.org/
112•uticus•6h ago•15 comments

We replaced RAG with a virtual filesystem for our AI documentation assistant

https://www.mintlify.com/blog/how-we-built-a-virtual-filesystem-for-our-assistant
185•denssumesh•1d ago•87 comments

Charge Robotics (YC S21) Is Hiring Software and Hardware Engineers

https://jobs.ashbyhq.com/charge-robotics
1•banks_h•1h ago

Samsung Magician disk utility takes 18 steps and two reboots to uninstall

https://chalmovsky.com/2026/03/29/samsung-magician.html
379•chalmovsky•5d ago•208 comments

How to Make a Sliding, Self-Locking, and Predator-Proof Chicken Coop Door (2020)

https://www.backyardchickens.com/articles/how-to-make-a-sliding-self-locking-and-predator-proof-c...
57•uticus•4h ago•27 comments

The house is a work of art: Frank Lloyd Wright

https://aeon.co/essays/frank-lloyd-wright-as-a-mirror-of-the-american-condition
8•midnightfish•41m ago•0 comments

Async Python Is Secretly Deterministic

https://www.dbos.dev/blog/async-python-is-secretly-deterministic
49•KraftyOne•4h ago•23 comments

Iran Strikes Leave Amazon Availability Zones "Hard Down" in Bahrain and Dubai

https://www.bigtechnology.com/p/iran-strikes-leave-amazon-availability
66•upofadown•1h ago•34 comments

A Taxonomy of Interiors

https://misfitsarchitecture.com/2026/03/29/a-taxonomy-of-interiors/
12•downweight•4d ago•0 comments

F-15E jet shot down over Iran

https://www.theguardian.com/world/2026/apr/03/us-fighter-jet-confirmed-shot-down-over-iran
303•tjwds•7h ago•707 comments

DCJ11Hack+ – DEC PDP/11 based homebrew computer

https://codeberg.org/TechPaula/DCJ11HackPlus
14•zdw•3d ago•0 comments

Build your own Dial-up ISP with a Raspberry Pi

https://www.jeffgeerling.com/blog/2026/build-your-own-dial-up-isp-with-a-raspberry-pi/
89•arjunbajaj•7h ago•20 comments

Automatic Textbook Formalization

https://github.com/facebookresearch/repoprover
21•tzury•2h ago•7 comments

April 2026 TLDR Setup for Ollama and Gemma 4 26B on a Mac mini

https://gist.github.com/greenstevester/fc49b4e60a4fef9effc79066c1033ae5
280•greenstevester•13h ago•111 comments

Show HN: Ismcpdead.com – Live dashboard tracking MCP adoption and sentiment

https://ismcpdead.com
18•sagirodin•3h ago•13 comments

The Hardest Document Extraction Problem in Insurance

https://www.furtherai.com/engineering-blogs/hardest-document-extraction-problem-in-insurance
15•sgondala_ycapp•1h ago•0 comments

Show HN: TurboQuant for vector search – 2-4 bit compression

https://github.com/RyanCodrai/py-turboquant
83•justsomeguy1996•5d ago•5 comments

SSH certificates: the better SSH experience

https://jpmens.net/2026/04/03/ssh-certificates-the-better-ssh-experience/
199•jandeboevrie•13h ago•83 comments

Firm boosts H.264 streaming license fees from $100k up to staggering $4.5M

https://www.tomshardware.com/service-providers/streaming/h264-streaming-license-fees-jump-from-10...
123•MaximilianEmel•4h ago•51 comments

A Recipe for Steganogravy

https://theo.lol/python/ai/steganography/seo/recipes/2026/03/27/a-recipe-for-steganogravy.html
129•tbrockman•5d ago•29 comments

Linux Running in a PDF (2025)

https://linux.doompdf.dev/linux.pdf
70•matthewsinclair•3d ago•19 comments

What Category Theory Teaches Us About DataFrames

https://mchav.github.io/what-category-theory-teaches-us-about-dataframes/
173•mchav•5d ago•60 comments

Update on the eBay Scam

https://kevquirk.com/update-on-the-ebay-scam
27•speckx•4h ago•30 comments

ESP32-S31: Dual-Core RISC-V SoC with Wi-Fi 6, Bluetooth 5.4, and Advanced HMI

https://www.espressif.com/en/news/ESP32_S31_Release
195•topspin•5d ago•112 comments