| From: | Michael Fuhr <mike(at)fuhr(dot)org> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Tatsuo Ishii <ishii(at)postgresql(dot)org>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: What is the maximum encoding-conversion growth rate, anyway? |
| Date: | 2007-05-29 14:34:11 |
| Message-ID: | 20070529143411.GA70525@winnie.fuhr.org |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Tue, May 29, 2007 at 10:00:06AM -0400, Tom Lane wrote:
> In practice though, I find it hard to imagine a pair of encodings for
> which the growth rate is more than 3x. You'd need something that
> translates a single-byte character into 4 or more bytes (pretty
> unlikely, especially considering we require all these encodings to be
> ASCII supersets); or something that translates a 2-byte character into
> more than 6 bytes.
Many characters in the 0x80..0xff range of single-byte encodings
like LATIN1 become four bytes in GB18030 (e.g., LATIN1 f1 = GB18030
81 30 8a 39). PostgreSQL doesn't currently support such conversions
but it's something to be aware of.
--
Michael Fuhr
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Jeroen T. Vermeulen | 2007-05-29 15:02:25 | Re: What is the maximum encoding-conversion growth rate, anyway? |
| Previous Message | Zdenek Kotala | 2007-05-29 14:14:34 | Re: Users specific to a Database |