23. Oct. 2008

General Differences between DB2 and Oracle

  • A DB2-Instance can serve several independent  DB2-databases
  • One DB2-Instance is referenced by an OS-User with similar name
  • The home directory of the OS-User is the instance home directory
  • DB2 does not know about user administration
  • DB2 user are authenticated by Operating System Users or
    Directory Services e.q. NIS, LDAP,AD
  • There is one Alertlog per Instance called db2diag.log
  • A DB2-database is started on demand by the first connection
  • there is no ROLLBACK-/UNDO-Management in DB2
    • Oracle:   Multi Version Read Consistency
    • DB2:       ANSI standard Isolation levels
                     Repeatable Read, Read Stability, Cursor Stability
                     and Uncommitted Read (Dirty Read)

    Further Information about: DB2 Online Documentation