I guess this represents most exactly what this professor is thinking
about -- being able to create methods and types with methods which can
be nested -- but syntactical details are of secondary importance.
All the best, Nick
On 02/01/2011 05:43 AM, Pavel Stehule wrote:
> it is part of ANSi SQL 2003
> 2011/2/1 Pavel Stehule<pavel(dot)stehule(at)gmail(dot)com>:
>> 2011/2/1 Robert Haas<robertmhaas(at)gmail(dot)com>:
>>> On Mon, Jan 31, 2011 at 5:09 PM, Nick Rudnick<joerg(dot)rudnick(at)t-online(dot)de> wrote:
>>>> Interesting... I remember that some years ago, I fiddled around with
>>>> functions, operators etc. to allow a method like syntax -- but I ever was
>>>> worried this approach would have serious weaknesses -- are there any
>>>> principal hindrances to having methods, if no, can this be implemented in a
>>>> straightforward way?
>>> It would help if you were a bit more specific. Do you mean you want
>>> to write something like foo.bar(baz) and have that mean call the bar
>>> method of foo and pass it baz as an argument?
>>> If so, that'd certainly be possible to implement for purposes of a
>>> college course, if you're so inclined - after all it's free software -
>>> but we'd probably not make such a change to core PG, because right now
>>> that would mean call the function bar in schema baz and pass it foo as
>>> an argument. We try not to break people's code to when adding
>>> nonstandard features.
>> I has not a standard, so I am not sure what is in standard and what
>> not. It was a popular theme about year 2000 and OOP was planed to
>> SQL3. You can find a some presentation from this time. Oracle
>> implemented these features.
>> J. Melton: SQL:1999: Understanding Object-Relational and
>> Other Advanced Features, Morgan Kaufmann, 2003.
>> CREATE METHOD next_color (n INT)
>> RETURNS INT
>> FOR colored_part_t
>> RETURN SELF.color_id + n
>> SELECT partno, color_id, DEREF(oid).next_color(1) AS next
>> FROM colored_parts
>> some other databases implemented a dereferenced data (it's not only
>> Oracle's subject)
>> Probably DB2 implements this functionality too. See doc for CREATE
>> TYPE statement, REF USING, NOT FINAL, method specification
>> CREATE TYPE type-name
>> METHOD attribute-name()
>> RETURNS attribute-type
>> these features are very nice - but is not well documented and probably not used.
>>> Robert Haas
>>> EnterpriseDB: http://www.enterprisedb.com
>>> The Enterprise PostgreSQL Company
In response to
pgsql-hackers by date
|Next:||From: Nick Rudnick||Date: 2011-02-01 21:27:47|
|Subject: Re: [pgsql-general 2011-1-21:] Are there any projects interested
in object functionality? (+ rule bases)|
|Previous:||From: Kevin Grittner||Date: 2011-02-01 21:08:54|
|Subject: Re: [pgsql-general 2011-1-21:] Are there any projects interested in object functionality? (+ rule bases)|