Re: using a plpgsql function argument as a table column.

CREATE OR REPLACE FUNCTION test(year VARCHAR)
RETURNS TABLE (agencycode INT, bureaucode INT, acctname VARCHAR, beacat
VARCHAR, onoffbudget VARCHAR, val INT)
AS $$
BEGIN
RETURN QUERY SELECT t1.agencycode, t1.bureaucode, t1.acctcode,
t2.beacat, t2.onoffbudget, t2.XXXXXX  FROM allnames AS t1
JOIN total AS t2 on t1.agencycode = t2.agencycode and t1.bureaucode =
t2.bureaucode and t1.acctcode = t2.acctcode
WHERE t2.XXXXXXX != 0  ORDER BY t1.agencycode, t1.bureaucode, t1.acctcode;
END; $$
LANGUAGE 'plpgsql';

I want to replace XXXXXXX with the argument year.
I hard coded the XXXXXX with 'y2016' and I get back a table

Would something like 't2.'||(year)|| work?

On 08/28/2018 10:24 PM, Thomas Boussekey wrote:
> Hello,
>
> Yes, you can :-)
>
> Using a functional that returns a table, like in the following
> example:
> http://www.postgresqltutorial.com/plpgsql-function-returns-a-table/
>
> You will have to generate a dynamic sql statement for querying your
> table with the accurate WHERE clause. Like in this example:
> https://stackoverflow.com/questions/12780275/dynamic-sql-query-in-postgres
>
> Hope this helps
> Have a nice day
> Thomas
>
> Le mer. 29 août 2018 à 07:11, ss <ss(at)tuxclub(dot)org
> <mailto:ss(at)tuxclub(dot)org>> a écrit :
>
> I have a table with many years as columns. y1976, y2077, .. ,
> y2019,y2020 I want to dynamically return a column from a function.
>
>
> select * from FUNCTION('y2016') .....
>
> select t1.cola t1.colb, t1.colc, t2.y2016 from ..... Where
> t2.y2016 != 0;
>
> or if I select year y2012 I want FUNCTION('y2012')
>
> select t1.cola t1.colb, t1.colc, t2.y2012 from ..... Where
> t2.y2012 != 0;
>
>
> to generalize
>
> select * from FUNCTION( year_column )
>
> select t1.cola t1.colb, t1.colc, t2.year_column from ..... Where
> t2.year_column != 0;
>
> is it possible? if so how?
>
>