FInding "corrupt" values in UTF-8 tables (regexp question, I think) - Mailing list pgsql-general

From Phoenix Kiula
Subject FInding "corrupt" values in UTF-8 tables (regexp question, I think)
Date
Msg-id e373d31e0708170858o51492ebaq53283c14273fcdf2@mail.gmail.com
Whole thread Raw
Responses Re: FInding "corrupt" values in UTF-8 tables (regexp question, I think)  (Manuel Sugawara <masm@fciencias.unam.mx>)
Re: FInding "corrupt" values in UTF-8 tables (regexp question, I think)  (Michael Glaesemann <grzm@seespotcode.net>)
List pgsql-general
I'm noticing that some of my data has been imported as junk text:

For instance:

    klciã«"

What would be the SQL to find data of this nature? My column can only
have alphanumeric data, and the only symbols allowed are "-" and "_",
so I tried this regexp query:

    select id, t_code
    from traders
    where t_code ~ '[^A-Za-z1-9\-]'
    limit 100;

But this starts to return values such as "181xn-807199" which is valid
as per the above regexp? Also, when I try to include the underscore,
as follows...

    select id, t_code
    from traders
    where t_code ~ '[^A-Za-z1-9\-\_]'
    limit 100;

This gives me an error: "ERROR:  invalid regular expression: invalid
character range".

What am I missing? Does this have something to do with erroneous
encodings? I want my data to be utf-8 but I do want to find it with
latin1 queries when the text in columns is supposed to be only latin1
characters! Or is "a-z" in utf-8 considered different from "a-z" in
latin1?

pgsql-general by date:

Previous
From: "Pavel Stehule"
Date:
Subject: Re: why it doesn't work? referential integrity
Next
From: Manuel Sugawara
Date:
Subject: Re: FInding "corrupt" values in UTF-8 tables (regexp question, I think)