Re: postgres limitation

How about the full answer? I think Tom did a fantastic job of writing up,
be a shame to make it go to waste for brevity? :(

On Sat, 27 Jan 2001, Bruce Momjian wrote:

> OK, how is this?
>
>
> These are the limits:
>
> Maximum size for a database? unlimited (60GB databases exist)
> Maximum size for a table? 64 TB on all operating systems
> Maximum size for a row? unlimited in 7.1 and later
> Maximum size for a field? 1GB in 7.1 and later
> Maximum number of rows in a table? unlimited
> Maximum number of columns in a table? 1600
> Maximum number of indexes on a table? unlimited
>
> Of course, these are not actually unlimited, but limited to
> available disk space and memory/swap space. Performance may
> suffer when these values get unusually large.
>
> ---------------------------------------------------------------------------
>
>
>
> > Bruce, I think section 4.6 of the FAQ is a tad on the short and overly
> > optimistic side. Here's a set of more precise statements ...
> >
> >
> > 4.6) What is the maximum size for a row, table, database?
> >
> > Maximum size for a database?
> >
> > Effectively unlimited, although you may see performance problems with
> > more than a few thousand tables in a database, depending on how
> > gracefully your filesystem copes with directories containing many files.
> >
> > Maximum size for a table?
> >
> > 2G blocks, hence 16 to 64 terabytes depending on the BLCKSZ
> > configuration constant. (If someone were to run around and make sure
> > all the block-number arithmetic is unsigned, we could claim 4G blocks,
> > but I think it's not all unsigned now...)
> >
> > Maximum size for a row?
> >
> > See limits on field size and number of columns.
> >
> > Maximum size for an individual field value?
> >
> > Field values are limited to 1Gb, and in practice are more tightly
> > limited by memory/swap space available to a backend; a field value that
> > is a large fraction of the maximum process memory size will probably
> > cause out-of-memory failures.
> >
> > Maximum number of columns in a table?
> >
> > 1600. In practice probably quite a bit less, even with TOAST, since the
> > master tuple still has to fit in a block. If all the columns are large
> > (toastable) then at most you could fit about 250 columns with BLCKSZ=8K,
> > since an out-of-line TOAST value pointer takes 32 bytes. On the other
> > hand, 1600 int4 columns would fit easily.
> >
> > Maximum number of rows in a table?
> >
> > No specific limit. Note however that the COUNT() function currently
> > uses an int4 counter, so will give bogus results for more than 2G rows.
> >
> > Maximum number of indexes on a table?
> >
> > No limit.
> >
> > regards, tom lane
> >
>
>
> --
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
> + If your life is a hard drive, | 830 Blythe Avenue
> + Christ can be your backup. | Drexel Hill, Pennsylvania 19026
>

Marc G. Fournier ICQ#7615664 IRC Nick: Scrappy
Systems Administrator @ hub.org
primary: scrappy(at)hub(dot)org secondary: scrappy(at){freebsd|postgresql}.org