Обсуждение: postgres functions(.so)

Can anybody help me?
The question is: Is it possible to write
postgres function on C/C++ that selects
some tables of a database ?

More detailed description.
Suppose I have database with tables A, B.
I've written program on C++ with 'main' function
that reads tables A, B and returns some value, e.g. integer.
Now I'd like to implement the same actions as postgres
function (e.g. as .so module).

Is it possible ?

I know:
    1) How compile C/C++ code to .so
    2) How to CREATE FUNCTION .....
I don't know:
    1) Is it possible to postges function
       to read tables of the database
    2) If possible, how it should be done?
    3) Which restrictions applicable to .so
       functions ?

If you know examples those do something similar,
please let me know.

Any help will be appreciated.

Thanks
 

-- 
Vladimir Zolotych                         gsmith@eurocom.od.ua

You can read a brief introduction in chapter 19 of my book at:

    http://www.postgresql.org/docs/awbook.html

Sounds like you want to use the SPI interface.  See the PostgreSQL
manuals for more information.

[ Charset KOI8-R unsupported, converting... ]
>   Hello
>
> Can anybody help me?
> The question is: Is it possible to write
> postgres function on C/C++ that selects
> some tables of a database ?
>
> More detailed description.
> Suppose I have database with tables A, B.
> I've written program on C++ with 'main' function
> that reads tables A, B and returns some value, e.g. integer.
> Now I'd like to implement the same actions as postgres
> function (e.g. as .so module).
>
> Is it possible ?
>
> I know:
>     1) How compile C/C++ code to .so
>     2) How to CREATE FUNCTION .....
> I don't know:
>     1) Is it possible to postges function
>        to read tables of the database
>     2) If possible, how it should be done?
>     3) Which restrictions applicable to .so
>        functions ?
>
> If you know examples those do something similar,
> please let me know.
>
> Any help will be appreciated.
>
> Thanks
>
>
> --
> Vladimir Zolotych                         gsmith@eurocom.od.ua
>
>


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