[ot] pg_restore > ascii dump size

Peter Corlett abuse at cabal.org.uk
Wed Nov 22 17:45:43 GMT 2006


On Wed, Nov 22, 2006 at 04:47:09PM +0000, Raf wrote:
[...]
> Fine. Now we pg_restored that dump. It's still restoring and the size of
> the physical database now exceeds 15GB again. This is from a 4GB dump. I
> don't think that the DB is so badly designed that this would result from
> badly chosen data types in the schema.

That doesn't surprise me at all. ASCII is in fact quite a rather compact and
efficient form for storage of data. Integers are usually represented with
four bytes in a binary format, but typical data consists of lots of small
integers which will fit in two or three bytes. Once you throw in alignment
requiremens, the space required for a binary format may increase further.

And then your database has indexes. These can often be nearly as large as
the table itself, but aren't dumped because they can be recreated from the
ASCII form.

Anyway, if you want a database where you can micromanage the size of words
and have them packed tightly, you know where MySQL is. Just remember what
happened to Slashdot :)

> Not sure where this is coming from. Has anyone ever seen this. Would you
> like to join the "I hate Postgres" society?

Remember the ASR mantra: "all software sucks".



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