Talk About Network

Google


Register and Login
Nick
Password
Register create new account Sign up is FREE and you can post replies, new topics, bookmark posts and more!
Recover lost password


Data Bases > Pgsql Bugs > Re: BUG #4083: ...
Latest [ Topics | Posts ] Archive Post A New Topic Post a Reply
<< Topic < Post Post 1 of 3 Topic 3675 of 3899
Post > Topic >>

Re: BUG #4083: Return type of MAX and MIN of a VARCHAR column is

by pgsql-002@[EMAIL PROTECTED] (Pedro Gimeno) Apr 2, 2008 at 11:14 AM

Peter Eisentraut wrote:

> Tom Lane wrote:
> > I think you need to file a bug with Zeos to fix whatever their
> > problem is with text.
>
> Well, to be fair, type text is not SQL standard.  But surely Zeos
> won't get very far with this superstrict typing approach.  At least a
> little bit more context might help us understand.

Sure. Zeos allows connection to multiple servers, not just PostgreSQL;
for example, Firebird, MySQL and MSSQL.

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
sup****ted servers, which are graphically associated with single-line
edit controls.

On the other side, Zeos (as BDE did before as well as others) recognizes
that many servers have mechanisms for allowing fields with texts longer
than 255 characters and adds sup****t for them; for example in Firebird
the type is BLOB SUB_TYPE TEXT and in MySQL it's TEXT. It assumes that
PostgreSQL's TEXT type falls into that category and associates it with a
"large text" type rather than "short text". The sup****t for them is
quite limited, as they are a kind of "largest common divisor" of the
capabilities of the sup****ted servers.

I think, but I'm not sure, that even the ODBC standard makes such
distinction between short and large text fields.

BTW, of course Tom is right in that most operators return TEXT and not
VARCHAR; I just stumbled upon this problem in a query that used MAX().

-- Pedro Gimeno

-- 
Sent via pgsql-bugs mailing list (pgsql-bugs@[EMAIL PROTECTED]
)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-bugs
 




 3 Posts in Topic:
Re: BUG #4083: Return type of MAX and MIN of a VARCHAR column is
pgsql-002@[EMAIL PROTECTE  2008-04-02 11:14:56 
Re: Re: BUG #4083: Return type of MAX and MIN of a VARCHAR
alvherre@[EMAIL PROTECTED  2008-04-02 11:05:13 
Re: Re: BUG #4083: Return type of MAX and MIN of a VARCHAR
pgsql-002@[EMAIL PROTECTE  2008-04-02 18:40:29 

Post A Reply:
  Go here to Signup

AddThis Feed Button


About - Advertising - Contact - Frequently Asked Questions - Privacy Policy - Terms of Use - Signup

Contact
tan13V112 Sun Jul 6 0:57:54 CDT 2008.