Databases Have a Lot of Data
A recurring theme in the ongoing coverage of Sam Bankman-Fried's trial has been his apparent recklessness. One particularly popular anecdote being his...
Representing Columns in Query Optimizers
Query optimizers must have a way to internally represent their plans. This is query planning's version of an "intermediate representation," or IR. There's a...
Why Are Query Plans Trees?
Looking at just about any database's EXPLAIN output will reveal that generally, queries get compiled into tree-shaped plans, rather than general cyclic...
Internal Affairs
There is a trick called string interning that is well known to compiler authors, and sometimes shows up in other places as well. It's used to change the...
Unity and VLDB Reading List #2
Normies Learn Software Licensing If you're a software person and at all plugged in to the world of video games, you might have watched in horror as Unity...
VLDB Reading List #1: TUM Edition
VLDB just happened! And I have been going through some of the papers that caught my eye. As it turns out, this week is TUM week. What Modern NVMe Storage Can...
The Problem with Declarativity
IN or OR There was a very nice blog post from OtterTune [1] recently, digging into some of the quirks of the way Postgres executes a particular query: Query...
Hard and Soft Statistics
One lens I've found satisfying for "what is a query planner" is that it's a tool for "approximating domain knowledge." By that I mean, someone who knows...
The Halloween Problem
What if you had an isolation anomaly with yourself? If you're receiving this as an email, thank you for entrusting me with your email address, I know that's...