~/notes/databases
#databases
Problems I ran into, what I tried, and what I learned along the way. Some are finished stories, some are notes I'm still adding to.
- VACUUM in PostgreSQL If PostgreSQL never overwrites a row, where do all the old versions go? And why didn't my table shrink after I deleted most of it?
- Understanding MVCC in PostgreSQL What does transaction B see while transaction A is changing the same row? I finally sat down to find out what happens under a simple UPDATE.
- Do I really need to think about isolation levels? Just querying the database as usual works, right up until two people try to book the last ticket at the same time.