Re: Querying Headers

[pw <p(dot)willis(at)telus(dot)net>]

pw wrote:
> Hello,
>
> I am curious if there is a postgresql function that will
> return a list of header names based on an input query text.
>
> ie:
>
>
> select return_headers("SELECT name, date, shape FROM some_table;") as 
> headers;
>
> returning:
>
> headers
> -------
> name
> date
> shape
>
>
> Thanks for any help.
>
> Pw

As a supplementary comment to this:
This information can be extracted from the pg_catalog
in several steps as follows:

CREATE VIEW testview AS (SELECT name, date, shape FROM some_table);

SELECT distinct attname FROM pg_attribute, pg_class, testview WHERE 
attrelid=pg_class.oid AND pg_class.relname='testview';

/*GET THE COLUMN HEADERS HERE AND RETURN THEM*/

DROP VIEW testview;

I was however hoping someone had already created a
function that was standard.


ie:
CREATE FUNCTION return_header_names(text) RETURNS SETOF string
    AS '
	CREATE VIEW testview AS ($1);
	SELECT distinct attname FROM pg_attribute, pg_class, testview WHERE 
attrelid=pg_class.oid AND pg_class.relname='testview';
	'
    LANGUAGE SQL
    IMMUTABLE
    RETURNS NULL ON NULL INPUT;


Thanks again,


Pw