Re: variable value in array_to_string

My bad on the back tick. No idea why it turned that way

OK got that David.

The idea is that I have the pk columns in an array which I would like to manipulate from the array itself rather than running same query variations multiple times

For example I get in foo

{item_id,show_id}

And from here on I was looking to get say

a.item_id , a.show_id

and all sort of variations

Thanks for help

On Nov 21, 2016, at 4:26 PM, David G. Johnston <david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

> On Mon, Nov 21, 2016 at 3:09 PM, Armand Pirvu (home) <armand(dot)pirvu(at)gmail(dot)com> wrote:
> Hi
>
> Is there anyway I can pass a variable in the array_to_string function ?
>
>
> ​Yes, just like you can pass variables to any other function.​..
>
>
> CREATE OR REPLACE FUNCTION test1 () RETURNS void AS $$
> ​​DECLARE
> foo text;
> foo1 text;
> begin
> execute
> 'select ARRAY( SELECT d.COLUMN_NAME::text from information_schema.constraint_table_usage c, information_schema.key_column_usage d '
> ||
> 'where c.constraint_name=d.constraint_name and c.table_name=d.table_name and c.table_schema='
> ||
> quote_literal(‘myschema')
> ||
> ' and c.table_schema=d.table_schema and c.constraint_name like '
> ||
> quote_literal('%_pkey%')
> ||
> ') ' into foo;
> raise notice '%', foo;
> foo1 :=ARRAY_TO_STRING(foo, ', ');
> raise notice '%', foo1;
> END;
> $$ LANGUAGE plpgsql ;
>
>
> The idea is that I want to slice and dice and not run the query x amount of times
>
>
> I would suggest you learn to use the "format()" function, EXECUTE USING,​ and dollar quoting.
>
>
> So, I copy-pasted your example and placed it into a DO block
>
> The character before "myschema" came out as a back-tick instead of a single-quote.
>
> array_to_string has the signature (text[], text) but you've defined foo as being just text. Changing that results in a query that executes - though given my system doesn't have conforming data I get no results.
>
> David J.