i've been browsing the documentation online, and i can't find where the storage layouts for tables and indexes are explained.
i'd like to be able to figure out, given a table or two with a simple schema (no ineritance) and some indexes, and a number of rows currently in these tables, how much disk space is being used. the underlying problem being worked here, by the way, is to come up with a task that monitors space used by the database so as to issue a warning of some sort when the partition upon which the database resides is getting full. i had originally used the statfs output from the (unix) os, but for this to accurately reflect the "used" space, i found i had to do a "vacuum full" and compress the database. i'd rather come up with a heuristic where i can take a number of rows (which i get from the reltuples column in pg_class, which seems to be accurate after running 'analyze') and multiply by some number i have calculated based on the table schema to get a fairly accurate guess at the real space used. any and all advice welcome, and thanks. pg ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
