Value of SV File_IO_Status in Table IO

On an Update or Delete, SV File_IO_Status will always return “CO SUCCESS” even if the update or delete is not successful because the record does not exist. Per Development, it is Working as Designed as stated in SAR 3434592.
According to SQL Database Standard, an Update or Delete is considered successful even when “zero” row records is returned by the Database Update or Delete.
The workaround is to issue a FetchSingle on the record to be updated/deleted and use the result of the SV File_IO_Status of the FetchSingle to issue the update or delete.
Source: EnterpriseOne Docs