Tham khảo sách 'less16_recovery_tb3', công nghệ thông tin, cơ sở dữ liệu phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Performing Database Recovery Oracle Database 10g: Administration Workshop I 16- Objectives After completing this lesson, you should be able to recover from the loss of a: Control file Redo log file Data file Oracle Database 10g: Administration Workshop I 16- Opening a Database To open a database: All control files must be present and synchronized All online data files must be present and synchronized At least one member of each redo log group must be present SHUTDOWN NOMOUNT MOUNT OPEN STARTUP Opening a Database As a database moves from the shutdown stage to being fully open, it performs internal consistency checks. The stages are: NOMOUNT: In order for an instance to reach the NOMOUNT (also known as STARTED) status, the instance must read the initialization parameter file. No database files are checked while the instance enters the NOMOUNT state. MOUNT: As the instance moves to the MOUNT status, it checks whether all control files listed in the initialization parameter file . | Performing Database Recovery Oracle Database 10g: Administration Workshop I 16- Objectives After completing this lesson, you should be able to recover from the loss of a: Control file Redo log file Data file Oracle Database 10g: Administration Workshop I 16- Opening a Database To open a database: All control files must be present and synchronized All online data files must be present and synchronized At least one member of each redo log group must be present SHUTDOWN NOMOUNT MOUNT OPEN STARTUP Opening a Database As a database moves from the shutdown stage to being fully open, it performs internal consistency checks. The stages are: NOMOUNT: In order for an instance to reach the NOMOUNT (also known as STARTED) status, the instance must read the initialization parameter file. No database files are checked while the instance enters the NOMOUNT state. MOUNT: As the instance moves to the MOUNT status, it checks whether all control files listed in the initialization parameter file are present and synchronized. If even one control file is missing or corrupt, the instance returns an error (noting the missing control file) to the administrator and remains in the NOMOUNT state. OPEN: When the instance moves from the MOUNT state to the OPEN state, it: Checks whether all redo log groups known to the control file have at least one member present. Any missing members are noted in the alert log. Oracle Database 10g: Administration Workshop I 16- Opening a Database Full Notes Page Opening a Database (continued) Verifies that all data files known to the control file are present unless they have been taken offline. Offline files are not checked until the administrator tries to bring them online. The administrator may take a data file offline and open the instance as long as the data file does not belong to the SYSTEM or UNDO tablespaces. If any files are missing, an error noting the first missing file is returned to the administrator and the instance remains in the MOUNT