Answer:- This can be achieved by fetching the records of one table into a new table using the INTO operator while fixing a WHERE clause to be false for all records. In this way, SQL prepares the new table with a duplicate structure to accept the fetched records. However, there are no records that will get fetched due to the WHERE clause in action. Therefore, nothing is inserted into the new table, thus creating an empty table. SELECT * INTO Students_copy FROM Students WHERE 1 = 2;

Answer:- Oracle is a company. Oracle is also a database server, which manages data in a very structured way. It allows users to store and retrieve related data in a multi-user environment so that the users can concurrently access the same data. All this is accomplished while delivering high performance. A database server also prevents unauthorized access and provides efficient solutions for failure recovery. A standby database is a database replica created by taking a backup of a primary database.

Answer:- An index is an optional structure associated with a table to have direct access to rows that can be created to increase the performance of data retrieval. An index can be created on one or more columns of a table.

Answer:- Indexes are used for the easy access of data. To increase the performance of retrieval data, Indexes are used. It helps to find the required data quickly without actually searching each row.

Answer:- Oracle is capable of maintaining and using indexes and Oracle automatically distributes the data into relevant indexes when any change is made in the table data.

Answer:- There are many databases available in the market. The commonly used databases are Oracle, IBM db2, Microsoft SQL Server, Microsoft Access, MySQL and SQLite, PostgreSQL, MariaDB.

Answer:- Below 5 are the physical components of Oracle Database: Data files Control files Redo log files Password files Parameter files

Answer:- A DBA has the authority to create new users, remove the existing users, or modify any of the environment variables or privileges assigned to other users. • Manage database storage • Administer users and security • Manage schema objects • Monitor and manage database performance • Perform backup and recovery • Schedule and automate jobs

Answer:- Tables Views Indexes Synonyms Sequences Tablespaces

Answer:- A synonym which is also known as an alias is an identifier that can be used to reference another database object in a SQL statement. A table, view, sequence are the types of database objects that can be created for a synonym.

Answer:- There are two types of Synonyms which are- Public and Private. A public synonym isn’t part of any schema. A public synonym is one that can be used by any database user. A private synonym does belong to a specific schema. In other words, when only the owner can access it, it is called a private synonym.

Answer:- The main four types of backups in Oracle are: (ⅰ) COLD Backup (ⅱ) HOT Backup (ⅲ) Import – Export Backup (ⅳ) RMAN Backup

Answer:- Hot backup is also recognized as an Online Backup because here the backup is taken while the database is active and running. And when the backup can only happen while the database is in shut down mode then it is called Cold Backup which can also be identified as Offline Backup.

Answer:- Database users’ passwords are stored in the database’s data dictionary. When a user attempts to log into the database, the user’s usernames and passwords are compared to the values contained in the database. The user is given database access only if the username and password match. The data dictionary is stored in the database and can be accessed as long as the database is available. The dictionary also contains the passwords for the administrators. The data dictionary would be unavailable until the database is locked. Since starting up a down database is one of the administrator’s jobs, there needs to be a way for them to log in even if the database is locked. That’s where the password file comes into the picture. A password file is an operating system file that is held on a separate disc from the database. It stores the username and password for users with the SYSDBA or SYSOPER privileges. And when the database is down, administrators with certain privileges are authenticated using the password files.