Re: postgreSQL UPPER Method is converting the character "µ" into "M"

On 2023-09-06 17:29:21 +0200, Francisco Olarte wrote:
> On Wed, 6 Sept 2023 at 16:40, Sai Teja <saitejasaichintalapudi@gmail.com> wrote:
> > Actually we are migrating the data from DB2 to postgreSQL. So in DB2
> > the upper method is converting µ as µ only but not as M.
> > So, while validating the data we have encountered this problem.
[...]
> Maybe because unicode has GREEK CAPITAL LETTER MU ( 924, which looks
> like capital M ), GREEK SMALL LETTER MU ( 956 ) and MICRO SIGN ( 181,
> which looks like small mu ) while windows-1252 only has 0xB6 as micro.
> OTOH Windows-1253 ( greek ansi ) has all three.
>
> If your small mu are really micro-sign ( which is suspected if youused
> 1252 ) maybe changing them to that helps ( but I do not have the
> resources to test that on hand ).

Nope, it doesn't:

hjp=> select chr(181) as micro, chr(956) as mu;
╔═══════╤════╗
║ micro │ mu ║
╟───────┼────╢
║ µ     │ μ  ║
╚═══════╧════╝
(1 row)

hjp=> select upper(chr(181)) as micro, upper(chr(956)) as mu;
╔═══════╤════╗
║ micro │ mu ║
╟───────┼────╢
║ Μ     │ Μ  ║
╚═══════╧════╝
(1 row)


(At least not on an Ubuntu 22.04 system using the en_US.UTF-8 locale).

IMHO uppercasing MICRO SIGN doesn't make much sense, but that was the
decision that either the libc maintainers ore the Unicode committee
made.

        hp

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   _  | Peter J. Holzer    | Story must make more sense than reality.
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