Hello, I'am currently trying to implement some simple disc space limitation
mechanism for my database. Database is partition based and insert-only - I
insert new rows to the current partition and drop oldest partition when
disc space limit exceeded.
Algorithm is quite simple and it seems it works but I must ensure two
assumptions to avoid extra VACUUM/ANALYZE calls:
1. pg_total_relation_size return predictable approximately correct table
size (apart from some preallocation) without subsequent
VACUUM/ANALYZE/anything call as long as I don't DELETE/UPDATE rows;
2. DROP/TRUNCATE table reclaim disc space without subsequent VACUUM;
These assumptions are correct? Is it fixed in doc if so?
