NULL BITMAP by Justin Jaffray
Archives
Search
Subscribe
Philosophy and Methodology of Experiments
March 10, 2025
Sometimes you have to do an experiment. This is rote, manual work that is chiefly concerned with data collection. I'm mostly talking about performance...
Chapters 1 & 2 of Feedback Control
March 3, 2025
Hello! I hope you all had a good weekend. This is the first "study group" issue where I will share thoughts on the first two chapters of Feedback Control for...
More Blind Writes and Merge Operators
February 24, 2025
Programming Note There is one week left to email me (firstname . lastname at gmail.com, or reply to this email) your thoughts on the first two chapters of...
What if SQL Was Informed by LSMs?
February 17, 2025
Programming Note: Feedback Control Study Group I'm hosting what I am calling a "study group" about feedback control, loosely backed by Feedback Control for...
Why Feedback Control Interests Me+Discussion Group
February 10, 2025
I got enough positive interest in some variety of book club that I would like to move forward with that. I want to discuss Feedback Control for Computer...
Are Correctness Conditions Descriptive or Prescriptive?
February 3, 2025
Please see the bottom of this issue for a programming note! Correctness conditions constrain the sequences of events that are allowed to occur in a system...
Trampolines for SQL
January 27, 2025
It is CIDR time and that means there is a lot of out-there papers in the world of databases to look at. If you are not familiar, CIDR is the Conference on...
A Review of Extensible Query Optimizers in Practice
January 20, 2025
My roommate and I are in a war with UPS. I came home the other day to find she’d left this note on our front door: It would appear she also has some kind of...
A Trick That Doesn't Work and a Trick That Does
January 13, 2025
Ancestry I came across a cool algorithm recently for being able to efficiently answer ancestor queries in a tree ("is x an ancestor of y"). The trick is to...
Channel Sharding in Go
January 6, 2025
It’s a common pattern in Go to fan out I/O-bound tasks to a bunch of worker Goroutines. We have some big batch of work that has to get done, and we dole it...
Coupled Code is Cool
December 30, 2024
Happy new year, nothing too deep this week because I am traveling. If you read NULL BITMAP this year you have my gratitude. Peace and love. One of the...
Git Workflow is Snapshot-Isolated
December 23, 2024
We are apparently continuing our series of posts borne from thinking about Amazon DSQL. Today we are talking about skew. Amy and Bill are two developers...
Why are Things Associative?
December 16, 2024
The big three algebraic properties that show up in the distributed systems literature are associative, commutativity, and idempotency (EYE-dem-po-ten-see)....
What are the Magical Clocks for?
December 9, 2024
At Re:Invent last week, AWS announced DSQL, their new serverless SQL database. As a fan of distributed SQL databases I have been enjoying reading about the...
Thoughts on DuckDB's Grammar Patching Thing
December 2, 2024
It is the job of modern programming languages to be amenable to abstractions. It should be easy for users to take a little bundle of functionality and reuse...
Fine! I'll Play With Skiplists
November 25, 2024
Follow me on Bluesky! A Log-Structured Merge tree, or LSM, is a popular data structure for storage engines. It’s what is used by RocksDB, which is sort of...
The Prequel to SQL is SEQUEL
November 18, 2024
Meta note: follow me on Bluesky if you are so inclined. I've been going through some historical stuff lately. Been on a history kick. We went to see the...
The CVM Algorithm
November 11, 2024
Everything you need to know about query planning can be understood from this query: SELECT * FROM xy WHERE y = 3 ORDER BY x Imagine we have two indexes, one...
How Many Grains of Sand are in a Pile
November 4, 2024
“This code’s no good,” says Pittsford, pointing at the screen: def update_and_get_balance(account, amount): database.debit(account, amount) return...
Adventures in Probability
October 28, 2024
I hope everyone had a good weekend. I went on a hike. It was great. Statistics One of my great school regrets, next to “taking three years of business...
Newer archives
Older archives