Final Day reveiw Flashcards
Which type of database backup can be performed while a database is online?
Inconsistent
What can be queried from a database while it is in the NOMOUNT state?
Instance parameters
Which process duplicates modified blocks from a buffer cache to files on disk?
Database Writer (DBWn)
In response to users’ complaints that the system is slow, a database administrator detects that a user is consuming too many resources.
Which parameter controls the use of service units?
COMPOSITE_LIMIT
What is the result of the CASCADE option when used with the DROP USER command?
All the user’s objects are removed from the database.
Which privilege is required to add a foreign key constraint to a table owned by another user?
REFERENCES
An administrator runs the following SQL statements:
CREATE USER HR_User IDENTIFIED BY ‘Password’ DEFAULT TABLESPACE DATA;
GRANT CREATE SESSION, CREATE TABLE to HR_User;
HR_User creates a new table in their own schema.
What happens when HR_User inserts a row into the new table?
The insert fails with an error for missing privileges on the DATA tablespace.
What is the NOMOUNT state in Oracle?
The NOMOUNT state is the initial state of an Oracle instance, in which the instance is started but the database is not mounted.
What does it mean for a database to be “mounted”?
When a database is “mounted,” it means that the instance is able to access the datafiles and control files of the database.
What can be done in the NOMOUNT state?
In the NOMOUNT state, the instance can perform tasks such as creating a new database or recovering an existing one.
What is the command to start an instance in NOMOUNT state?
The command to start an instance in NOMOUNT state is “STARTUP NOMOUNT”.
What is the command to mount a database?
The command to mount a database is “ALTER DATABASE MOUNT”.
What is the command to open a database?
The command to open a database is “ALTER DATABASE OPEN”.
What is the difference between mounting and opening a database?
Mounting a database makes it accessible to the instance, while opening a database makes it available for use by users.
What can be queried from a database while it is in the NOMOUNT state?
While the database is in the NOMOUNT state, you will not be able to query any data from the database as the database is not mounted, and the instance does not have access to the datafiles and control files of the database.
In NOMOUNT state, you can only query the information available in the data dictionary, such as the initialization parameters, backup and recovery information, and the structure of the database objects. However, you will not be able to access the data stored in the database tables.
You can also check the status of the background processes and the memory structures such as SGA, PGA etc.
Once the database is mounted and opened, you will be able to query the data in the database tables.
What is the MOUNTED state in Oracle?
The MOUNTED state is when the instance has successfully mounted the database, allowing the instance to access the datafiles and control files of the database.