Ahana Systems & Solutions Interview Questions and Answers

Experienced in RMAN for backup, recovery, and database maintenance in Oracle environments.

• Proficient in RMAN commands for full and incremental backups.

• Implemented RMAN scripts for automated backup processes.

• Utilized RMAN for point-in-time recovery scenarios.

• Monitored backup performance and optimized RMAN configurations.

• Conducted RMAN catalog management for efficient backup tracking.

Joins in SQL combine rows from two or more tables based on related columns.

• INNER JOIN: Returns records with matching values in both tables. Example: SELECT * FROM Orders INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;

• LEFT JOIN: Returns all records from the left table and matched records from the right table. Example: SELECT * FROM Customers LEFT JOIN Orders ON Customers.CustomerID = Orders.Custom...read more

A foreign key is a field in a table that links to the primary key of another table, establishing a relationship between them.

• Foreign keys enforce referential integrity between tables.

• Example: In a 'Orders' table, 'CustomerID' can be a foreign key referencing 'CustomerID' in a 'Customers' table.

• They help maintain consistent data across related tables.

• Foreign keys can be used to join tables in SQL queries.

A primary key uniquely identifies each record in a database table, ensuring data integrity and efficient retrieval.

• A primary key must contain unique values for each record.

• It cannot contain NULL values, ensuring every record is identifiable.

• A table can have only one primary key, which may consist of one or multiple columns (composite key).

• Example: In a 'Users' table, 'UserID' can be a primary key as it uniquely id...read more

Cryptography is the study and practice of techniques for securing information and communication.

• Cryptography involves transforming plaintext into ciphertext to protect data from unauthorized access.

• It includes various algorithms and protocols for encryption, decryption, and key management.

• Examples of cryptographic techniques include symmetric encryption (e.g., AES), asymmetric encryption (e.g., RSA), and hashing (...read more