There is a second approach, which I found here (from mmatt). Basically you call a function within Postgres (last argument specifies the number of columns).
select load_csv_file('myTable','C:/MyPath/MyFile.csv',24)
Here is mmatt's function code, which I had to modify slightly, because I am working on the public schema. (copy&paste into PgAdmin SQL Editor and run it to create the function)
CREATE OR REPLACE FUNCTION load_csv_file(
target_table text,
csv_path text,
col_count integer)
RETURNS void AS
$BODY$
declare
iter integer; -- dummy integer to iterate columns with
col text; -- variable to keep the column name at each iteration
col_first text; -- first column name, e.g., top left corner on a csv file or spreadsheet
begin
set schema 'public';
create table temp_table ();
-- add just enough number of columns
for iter in 1..col_count
loop
execute format('alter table temp_table add column col_%s text;', iter);
end loop;
-- copy the data from csv file
execute format('copy temp_table from %L with delimiter '','' quote ''"'' csv ', csv_path);
iter := 1;
col_first := (select col_1 from temp_table limit 1);
-- update the column names based on the first row which has the column names
for col in execute format('select unnest(string_to_array(trim(temp_table::text, ''()''), '','')) from temp_table where col_1 = %L', col_first)
loop
execute format('alter table temp_table rename column col_%s to %s', iter, col);
iter := iter + 1;
end loop;
-- delete the columns row
execute format('delete from temp_table where %s = %L', col_first, col_first);
-- change the temp table name to the name given as parameter, if not blank
if length(target_table) > 0 then
execute format('alter table temp_table rename to %I', target_table);
end if;
end;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
ALTER FUNCTION load_csv_file(text, text, integer)
OWNER TO postgres;
Note: There is a common issue with importing text files related to encoding. The csv file should be in UTF-8 format. However, sometimes this is not quite achieved by the programs, which try to do the encoding. I have overcome this issue by opening the file in Notepad++ and converting it to ANSI and back to UTF8.