Re: Re: BUG #4083: Return type of MAX and MIN of a VARCHAR column is TEXT - Mailing list pgsql-bugs

From Pedro Gimeno
Subject Re: Re: BUG #4083: Return type of MAX and MIN of a VARCHAR column is TEXT
Date
Msg-id 47F3B6FD.7080800@personal.formauri.es
Whole thread Raw
In response to Re: Re: BUG #4083: Return type of MAX and MIN of a VARCHAR column is TEXT  (Alvaro Herrera <alvherre@commandprompt.com>)
List pgsql-bugs
Alvaro Herrera wrote:

> Pedro Gimeno escribió:
>
>> Zeos (as well as the Borland Database Engine, which it just mimics in
>> this sense) assumes that VARCHAR fields in general (not just
>> PostgreSQL's) are textual fields with a limit of 255 characters for all
>> supported servers, which are graphically associated with single-line
>> edit controls.
>
> Oh, so if you have a column of type VARCHAR(1000) or anything longer
> than 255 chars it fails too?
>
> And I'd guess that if you have a varchar(255) column and store a value
> longer than 255 bytes (because there are many wide chars) it will fail
> as well.
>
> Both cases should really be tested and taken to Zeos if they fail.

I haven't tried. The 255 character limit may be a wrong assumption from
my side and not an actual Zeos limitation, but still VARCHAR fields are
treated as single-line edits and TEXT fields are treated as blob-like,
multiline texts. Anyway, in general Delphi does not do very well with
multibyte character sets, which by the way I'm not using. If it's
relevant for this bug report I can find out if Zeos has trouble with
>255 character varchar fields. Otherwise you may want to make the test
yourself and report to http://zeosbugs.firmos.at/ which is Zeos' bug
tracker. I don't use >255 VARCHAR fields for compatibility with other
servers.

-- Pedro Gimeno

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