Обсуждение: length() return wrong result

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Hi,

- From the documentation, length(string) is 'Number of characters in string'

But it didn't :

1/ in a LATIN9 database:

postgres=# show server_encoding;server_encoding
- -----------------LATIN9

postgres=# set client_encoding = utf8;
SET
postgres=# select length('é');length
- --------     1

postgres=# set client_encoding = latin9;
SET
postgres=# select length('é');length
- --------     2

2/ in a UTF8 database:

postgres=# show server_encoding;server_encoding
- -----------------UTF8

postgres=# set client_encoding = utf8;
SET
postgres=# select length('é');length
- --------     1

postgres=# set client_encoding = latin9;
SET
postgres=# select length('é');length
- --------     2





- --
Cédric Villemain
Administrateur de Base de Données
Cel: +33 (0)6 74 15 56 53
http://dalibo.com - http://dalibo.org
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Cédric Villemain wrote:
> - From the documentation, length(string) is 'Number of characters in string'
>
> But it didn't :
>
> 1/ in a LATIN9 database:
>
> postgres=# show server_encoding;
>  server_encoding
> - -----------------
>  LATIN9
>
> postgres=# set client_encoding = utf8;
> SET
> postgres=# select length('é');
>  length
> - --------
>       1
>
> postgres=# set client_encoding = latin9;
> SET
> postgres=# select length('é');
>  length
> - --------
>       2

I bet your console works in UTF-8, so setting client_encoding=latin9 is
not the right thing to do. If you replace "select length('é')" with
"INSERT INTO foo VALUES ('é')", and check the contents of the table with
SELECT * FROM foo afterwards, you'll see that the string is garbled in
the latter case, and indeed consists of two characters.

As you noticed, server_encoding makes no difference here.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com