Re: Add COPY statement inside sql function AND/OR call function within function

On 11/12/2013 12:56 PM, Johannes Björk wrote:
> Hi, Im hoping someone could help me with this. I am new to any kind of
> sql coding so bare with me.
>
> I have written the below working function which I would like to print to
> .csv file(s)
>
> |CREATE  FUNCTION  retrieve_info(input_method TEXT,  input_species TEXT)  RETURNS SETOF
> retrieve_info_tblAS  $$
>   SELECT  tblA.id,  tblA.method,  tblA.species,  tblA.location
>   FROM  tblA
>   WHERE  method=input_methodAND  species=input_species
>   GROUP  BY  id,  method,  species
>   ORDER  BY  location
> $$  LANGUAGE'sql';|
>
>
> *DUMMY DATA*
>
> tblA (filled)
>
> |create  table  tblA(id varchar(5)  PRIMARY  KEY,  method text,  species varchar(10),  location
> text);
> insert  into  tblAvalues  ('1a',  'mtd1',  'sp1',  'locA'),('1b',  'mtd1',  'sp2',  'locC'),('1c',
> 'mtd2',  'sp3',  'locB'),('1d',  'mtd1',  'sp1',  'locB'),('1e',  'mtd2',  'sp5',  'locA');|
>
> retrieve_info_tbl (empty)
>
> |create  table  retrieve_info_tbl(id varchar(5)  PRIMARY  KEY,  method text,  ind varchar(10),
> location text);|
>
> Calling function
>
> |SELECT  *  FROM  retrieve_info('mtd1','sp1');|
>
> *OUTPUT*
>
> |retrieve_info(mtd1,  sp3)
>
> id|  method|  ind|  location
> ----------------------------
> 1a|  mtd1|  sp3|  locA
> 1d|  mtd1|  sp3|  locB|
>
>
> Since I have not succeeded in this, I tried to work around it creating a
> function which called this function and printed the result to a .csv file.

It looks like it is succeeding, it returns a setof. What are you looking
to do?

>
> |CREATE  FUNCTION  print_out(x TEXT,  y TEXT)  RETURNS voidAS  $$
>   COPY(SELECT  *  FROM  retrieve_info(x,y))  TO  'myfilepath/test.csv'
>   WITH  CSV HEADER;
> $$  LANGUAGE'sql';|
>
> Calling nested function.
>
> |SELECT  *  FROM  print_out('mtd1','sp1');|
>
> |
>
> *OUTPUT*
>
> The above gives this |ERROR: column "x" does not exist SQL state: 42703
> Context: SQL function "print_out" statement 1|. However, when
> substituting x,y in print_out() with 'mtd1','sp1' the correct output is
> printed to test.csv
>
> I would really appreciate any pointers on either one of the above problems.


>
> Many thanks,
>
> Johannes
>
> |


--
Adrian Klaver
adrian.klaver@gmail.com