This function returns the n-th field from a given string divided by a delimiter.
Function Field(Source, Veldnummer, Delimiter)
substr(Source,
instr(DelimiterSourceDelimiter, Delimiter, 1, KolNr),
instr(DelimiterSourceDelimiter, Delimiter, 1, KolNr+1) - instr(DelimiterSourceDelimiter, Delimiter, 1, KolNr) -1)