How can I convert a date to string?

Question

I need to convert date from a DATS data type to a formatted string, like yyyy-mm-dd, at runtime.

Accepted Answer

Recent releases have a function module that allows generic formats

l_dat = '20110921'.
call function 'FORMAT_DATE_4_OUTPUT'
  exporting
    datin  = l_dat
    format = 'YYYY-MM-DD'
  importing
    datex  = l_str.

On older releases, that specific format YYYY-MM-DD, I think it has to be done by concatenation of substrings

concatenate l_dat(4) l_dat+4(2) l_dat+6(2) into l_str separated by '-'.