Re: confused on maximum characters - Mailing list pgsql-general

From Peter Eisentraut
Subject Re: confused on maximum characters
Date
Msg-id Pine.LNX.4.30.0108161844320.677-100000@peter.localdomain
Whole thread Raw
In response to confused on maximum characters  (roypgsqlgen@xemaps.com)
List pgsql-general
roypgsqlgen@xemaps.com writes:

> Looking at the docs Peter Eisentraut added this note at the bottom of the documentation for character data.
> ---
> The maximum value for "n" is 2147483648. The longest possible string is actually only about 1 GB, though. The storage
sizeof "(4+n)" is actually incorrect: char(n) really takes 4+n but varchar(n) and text take 4 plus the actual length of
thestored string. Long strings will actually be compressed by the system, though. 
> ---
>
> So does this mean I can specify very large varchar column types, like say varchar(1024)?

That's what that means.  (Although qualifying 1024 as very large is a
little out of proportion given the actual limits.)

> And what does he mean by 'Long strings will actually be compressed by the system'?

The system will compress long strings, so they don't take as much space on
disk.

--
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter


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