In this blog post, you’ll learn more about the Sybase Error Cannot add MIRROR file %3 to DAS dbspace %2 unless primary file %4 is empty or READONLY. %1 and the reason for receiving this error
Sybase SQL Error Message
Cannot add MIRROR file %3 to DAS dbspace %2 unless primary file %4 is empty or READONLY. %1
Reason for this Error
The mirror file cannot be added to the DAS dbspace primary file unless the primary file is empty or is READONLY. When a DAS dbspace is being initially set up, the files will all be empty. When a file primary file is CREATED with its MIRROR file, they both will be emtpy. But if a MIRROR file is added to an existing primary file (using the ALTER DBSPACE ADD EXISTING FILE syntax), data may need to be copied into the MIRROR and that case requires one first ALTER the primary dbfile to be READONLY, then do the add existing, and finally the primary file can be made READWRITE again.
