Passing a vector as argument in pl/r to initiate a for loop

Question

Need to initiate a for loop using a vector argument in pl/r. The code is as below:

DROP TYPE IF EXISTS tsdata CASCADE;
CREATE TYPE tsdata
AS
(
  a text,
  b text,
  c text,
  d text 
);


DROP FUNCTION IF EXISTS standard.create_pd_ts(data char, dimnames char);
CREATE FUNCTION standard.create_pd_ts(data char, dimnames char)
  RETURNS setof tsdata AS
$$
  drv <- dbDriver("PostgreSQL")
  conn <- dbConnect(drv, dbname = 'abc')

  iq <- paste0("select * from data")
  data <-dbGetQuery(conn, iq)
  data <- data.frame(coef_db_res_tab)

  for(i in 1:length(dimnames)) {
      var = dimnames [i]
      uniquedim= unique(data[,i])
      assign(paste0('dim',i),uniquedim)
     }
  ## save dimensions in a vector
  dimvec<-paste0('dim',1:length(dimnames),collapse = ',')

  tsdata <- eval(parse(text=paste0("expand.grid(", dimvec, 
  ",stringsAsFactors = FALSE)")))
  return(tsdata)

$$
LANGUAGE 'plr';

select
  (q).a,    
  (q).b,
  (q).c,
  (q).d
from
  (
    select * from standard.create_pd_ts(‘data’, 'c("a","b","c","d")')
  ) q ;

The motive of the function is to find unique values of column a, b, c and d; henceforth, store the values for the same in the dimvec vector, thereafter using the unique values of each column to expand grid to create all combinations. Tried a variety of things, but the for loop is not initiating. If I declare the dimnames vector inside the function, it works.

Also tried declaring as array, text, declaring as vector inside the function.

Any help is appreciated.

Answer 1

select
  (q).a,    
  (q).b,
  (q).c,
  (q).d
from
  (

select * from standard.create_pd_ts('data', ARRAY['a','b','c','d'])  
  ) q ;

This works for me. Thanks to my boss :)