# #databases Database systems in general: storage engines, transactions, consistency, and the trade-offs between them. > Canonical URL: https://sudohulk.com/tags/databases > Feed: https://sudohulk.com/tags/databases/rss.xml > Author: Vignesh Kumar A > Licence: CC BY 4.0. Quote freely, cite the canonical URL. --- ## Writing - [How PostgreSQL tells every connection its cache is stale](https://sudohulk.com/writing/postgres-cache-invalidation.md): Each PostgreSQL connection caches the catalog for itself. How a change is announced to all of them at commit through a shared ring, and what happens to a connection that falls behind. (2026-10-17; 19 min; part 5 of PostgreSQL internals, explained simply) ## Notes - [Full-page writes and torn pages](https://sudohulk.com/writing/full-page-writes-and-torn-pages.md): Why the first change to a page after a checkpoint carries the whole 8 KB page in WAL. (note, evergreen; planted 2026-09-22)