DTOC () without the second parameter is dependant of the SET DATE and SET CENTURY settings wich could lead to out of order records if a user with a different settings update the records. DTOC (, 1) or DTOS () return the same date format suitable for indexing (YYYYMMDD).

HTH

>Is there an advantage of using DTOS() over DTOC() or vise-versa when creating a compound index with a date field?