Re: Alternate methods for multiple rows input/output to a function.

On 5/28/19 7:36 AM, RAJIN RAJ K wrote:
> --> Function ' filter_id ' filters the ID's based on some conditions.
> --> Input is set of ID's. (Not directly taking the input since there is
> no provision to pass multiple rows to a function)

To be honest I cannot follow what you are trying to achieve below. I do
have one suggestion as to creating temp tables.

Why not use a CTE:

https://www.postgresql.org/docs/11/queries-with.html

in the function to build a 'temp' table on the fly?

>
> create function filter_id()
> return table (id bigint)
> begin
>
> --> Assuming input table is already created #temp_input_id
>
> retun query as select id
> from tbl a
> inner join
> #temp_input_id b on (a.id <http://a.id> = b.id <http://b.id>)
> where a.<conditions>;
>
> end;
>
>
> --> Calling Function:
>
> create function caller()
> return table (id bigint,col1 bigint, col2 bigint)
> begin
>
> --> do some processing
>
> --> Find out the input id's for filtering.
>
> --> Create temp table for providing input for the filtering function
>
> create temp table #TEMP1
> as select id from tbla........;
> (Cannot move the input id logic to  filter_function)
>
> --> calling the filter function
> create temp table #TEMP2
> as select * from filter_id(); --> This is a generic function used in
> many functions.
>
>
> return query
> as select a.*
> from tb3 a inner join tb4 inner join tb 5 inner join #TEMP2;
> end;
>
>
> Is there any alternate way of achieving this? Passing multiple records
> to a function im creating a temp table before invoking the function.
> For receiving an output of multiple rows i'm creating a temp table to
> reuse further in the code.
>
> Can this be done using Refcursor? Is it possible to convert refcursor to
> a temp table and use it as normal  table in query?
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com