Final answer:
To move a datafile online in Oracle 19c, you need to take the corresponding tablespace offline, move the datafile in the OS, and then rename the datafile in the control file using ALTER DATABASE. After moving, bring the tablespace back online.
Step-by-step explanation:
To move a datafile online in Oracle 19c, you can use the ALTER DATABASE command. The following steps outline the general process:
- Ensure that the database is in ARCHIVELOG mode and that you have a recent backup.
- Determine the datafile that needs to be moved and its current location.
- Use the ALTER TABLESPACE command to take the corresponding tablespace offline if it is not a system tablespace.
- Move the datafile to its new location at the operating system level.
- Issue the ALTER DATABASE command to rename the datafile in the control file.
- Bring the tablespace back online with the ALTER TABLESPACE command.
Example:
- ALTER TABLESPACE users OFFLINE;
- Move the datafile using OS commands.
- ALTER DATABASE RENAME FILE '/oldpath/users01.dbf' TO '/newpath/users01.dbf';
- ALTER TABLESPACE users ONLINE;
Remember to replace '/oldpath/users01.dbf' and '/newpath/users01.dbf' with your actual file paths. Always have a full backup of your database before performing such operations to prevent any data loss.