How to split comma separated string inside stored procedure?

Question

How to split comma separated string into strings inside store procedure and insert them into a table field?

Using Firebird 2.5

Answer 1

A similar solution I use, published a while ago by Jiri Cincura http://blog.cincura.net/232347-tokenize-string-in-sql-firebird-syntax/

recreate procedure Tokenize(input varchar(1024), token char(1))
returns (result varchar(255))
as
declare newpos int;
declare oldpos int;
begin
  oldpos = 1;
  newpos = 1;
  while (1 = 1) do
  begin
    newpos = position(token, input, oldpos);
    if (newpos > 0) then
    begin
      result = substring(input from oldpos for newpos - oldpos);
      suspend;
      oldpos = newpos + 1;
    end
    else if (oldpos - 1 < char_length(input)) then
    begin
      result = substring(input from oldpos);
      suspend;
      break;
    end
    else
    begin
      break;
    end
  end
end