Re: Regarding column reordering project for GSoc 2012

-----Original Message-----
From: Atri Sharma [mailto:atri(dot)jiit(at)gmail(dot)com]
Sent: 22 March 2012 09:20
To: 'Atri Sharma'
Subject: RE: [HACKERS] Regarding column reordering project for GSoc 2012

-----Original Message-----
From: Atri Sharma [mailto:atri(dot)jiit(at)gmail(dot)com]
Sent: 20 March 2012 23:05
To: 'Merlin Moncure'
Cc: 'Heikki Linnakangas'; 'Alvaro Herrera'; 'Daniel Farina'; 'Andrew
Dunstan'; 'Dave Page'; 'Pg Hackers'
Subject: RE: [HACKERS] Regarding column reordering project for GSoc 2012

-----Original Message-----
From: Merlin Moncure [mailto:mmoncure(at)gmail(dot)com]
Sent: 20 March 2012 22:50
To: Atri Sharma
Cc: Heikki Linnakangas; Alvaro Herrera; Daniel Farina; Andrew Dunstan; Dave
Page; Pg Hackers
Subject: Re: [HACKERS] Regarding column reordering project for GSoc 2012

On Tue, Mar 20, 2012 at 11:57 AM, Atri Sharma <atri(dot)jiit(at)gmail(dot)com> wrote:
>
>
> -----Original Message-----
> From: Merlin Moncure [mailto:mmoncure(at)gmail(dot)com]
> Sent: 20 March 2012 20:52
> To: Atri Sharma
> Cc: Heikki Linnakangas; Alvaro Herrera; Daniel Farina; Andrew Dunstan;
Dave
> Page; Pg Hackers
> Subject: Re: [HACKERS] Regarding column reordering project for GSoc 2012
>
> On Tue, Mar 20, 2012 at 6:58 AM, Atri Sharma <atri(dot)jiit(at)gmail(dot)com> wrote:
>> -----Original Message-----
>> From: Merlin Moncure [mailto:mmoncure(at)gmail(dot)com]
>> Sent: 20 March 2012 03:15
>> To: Heikki Linnakangas
>> Cc: Alvaro Herrera; Atri Sharma; Daniel Farina; Andrew Dunstan; Dave
Page;
>> Pg Hackers
>> Subject: Re: [HACKERS] Regarding column reordering project for GSoc 2012
>>
>> On Mon, Mar 19, 2012 at 2:49 PM, Heikki Linnakangas
>> <heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
>>> On 19.03.2012 21:29, Alvaro Herrera wrote:
>>>>
>>>>
>>>> Excerpts from Atri Sharma's message of lun mar 19 16:20:09 -0300 2012:
>>>>
>>>>> I was just going through PGfoundry and I think I will be able to work
>>>>> on the PL/Java project.Please let me know If I can proceed further on
>>>>> ot for GSOC and also,if currently there is any work that needs to be
>>>>> done on PL/java.
>>>>
>>>>
>>>> Hm, I'm not sure on PL/Java.  As far as I know, it is a dead project.
>>>
>>>
>>> I haven't followed PL/java either, but it doesn't look quite dead to me.
>> The
>>> last release was in September 2011, and there are active discussions on
>> the
>>> mailing lists. If it's not completely up-to-date with latest JDK and
>>> PostgreSQL releases, perhaps bringing it up-to-date and then adding some
>>> missing functionality would be a useful GSoC project.
>>>
>>> I would suggest that you ask on the pl/java mailing list if there is
>>> something suitable for a GSoC project there, and if one of the pl/java
>>> developers would be willing to mentor.
>>
>> pl/java works pretty well and is somewhat widely used although it
>> might need some more active maintainers.  just jumping into the
>> project and nailing some old bugs and getting the juices flowing would
>> be a tremendous help, as well as the less glamorous work of
>> documentation and regular status updates.
>>
>> one pl/java based project that IMO is just screaming to be done is a
>> pl/java based FDW (wrapping JDBC) that would approximately reproduce
>> dblink...maybe with some extra features geared towards ETL type jobs
>> like a row based callback for transformations in java.
>>
>> Merlin
>>
>>
>> ---------------------------
>> Hi Merlin
>>
>> Thanks for the idea.
>>
>> Could you please elaborate more on the project idea? It would be a great
>> help for me.
>
>> sure:
>> first start here: http://wiki.postgresql.org/wiki/Foreign_data_wrappers
>> and take a look at all the various fdw projects.  they all utilize the
>> high level interfaces that postgresql provides to incorporate external
>> datasources and expose them you can query them as if they were views
>> or tables.  as you can see, this interface is popular with the
>> proliferation of projects to expose this or that.  what i'm thinking
>> is you make a fdw that invokes pl/java routines that make jdbc calls
>> out to external databases.  for fetching data and building sets.  as
>> long as you stick to vanilla jdbc calls, you then have a fdw that can
>> gather data from pretty much anything you can access via jdbc url
>> which is quite nice.
>
>> The fdw API is a C api, so you need to figure out how to proxy to your
>> pl/java calls where the real work is done -- I  haven't done that so
>>I'm not sure if this is even technically feasible.  If you can make
>> SPI calls from your fdw routines, that's one path through.   Tou have
>> lots of previous work to crib from though and hopefully there's a path
>> through.  As far as the ETL stuff I was talking about -- that was just
>> me thinking out loud...better to just get the basic mechanics working
>> up front..  For now, if you're interested in doing this, start
>> thinking about how to marry the fdw interface to pl/java...one you get
>> 'hello world' there, it's all about where you want tot take it.
>
>> This is an interesting project -- you should entertain no illusions of
>> it making it into core, but if done right and completed it will raise
>> visibility of both pl/java and postgresql.
>
>> Merlin
>
>
>
-----------------
Hi Merlin,

Please let me know how to proceed further.

Waiting for your reply,

Atri