Re: 7.4: CHAR padding inconsistency

Troels Arvin wrote:
> Hello,
>
> I read about the padding-of-CHAR-values changes in the release notes for
> 7.4.
>
> Making PostgreSQL less standard compliant is sad; I also disagree
> with the statement that trimming of trailing white-space is what people
> expect.
>
> What's worse, and this may be classified as an error:
>
> create table chartest(col char(10) not null);
> insert into chartest values ('AAA');
>
> select character_length(col) from chartest;
> character_length
> ------------------
> 10
>
> select character_length(col || 'hey') from chartest;
> character_length
> ------------------
> 6
>
> SELECT CHARACTER_LENGTH(col) <
> CHARACTER_LENGTH(col||'hey') from chartest;
> ?column?
> ----------
> f
>
> The last two results are horrifying, in my opinion, especially when you
> consider them in concert: Concatenating a value with another value
> decreases its length...

Horrifying?

Anyway, what did you want it to output? "AAA hey"? We could do
that, but I assume most people wouldn't expect that output? If you use
literals it does work:

test=> SELECT 'aaa ' || 'bb';
?column?
----------
aaa bb
(1 row)

I tried this and it clipped too:

test=> SELECT CAST('aa ' AS CHAR(10)) || 'b';
?column?
----------
aab
(1 row)

How do other databases handle this?

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