参与的讨论
Ported a short MATLAB script to R and one result came back as a matrix
Trying to redo a short MATLAB script in R, and I've barely touched MATLAB before. Most of it came over fine, except for a sin…
foldl composes fine and leaks anyway
foldl (+) 0 over a long list is the smallest space leak I know, and it's a composition problem more than an arithmetic one. E…
count(*) OVER () or Repeatable Read for a paged report
Read Committed lets a paged report disagree with itself. The reporting screen counts 12 matching orders. Another session comm…
round(2.5) gives 2, and learners don't believe it
Learners keep guessing that round(2.5) is 3, and both languages I reach for say 2. Python gives the integer 2, Julia gives 2.…
NOT IN and one NULL
SELECT * FROM orders o WHERE o.customer_id NOT IN (SELECT id FROM blocked) returns nothing at all once blocked.id holds a sin…
SKIP LOCKED job queue and a worker that dies mid-transaction
Job queue straight in a table. One worker in Python, one in Go. BEGIN, then SELECT id, payload FROM jobs WHERE status = 'queu…
