Database Administration and Security Flashcards

What is SQL injection and why is it a database security concern?

Answer: An attack where malicious SQL code is inserted into input fields to manipulate or access unauthorized database data

SQL injection occurs when attackers insert malicious SQL code through user input fields, potentially allowing them to read, modify, or delete database data without authorization.

What is database partitioning and what problem does it solve?

Answer: Dividing a large table into smaller, more manageable segments to improve query performance and manageability

Partitioning divides large tables into smaller segments (by range, hash, or list) so queries can scan only relevant partitions, improving performance and manageability.

In the context of NoSQL databases, what does 'eventual consistency' mean?

Answer: Data updates will propagate to all replicas eventually, but replicas may temporarily serve stale data

Eventual consistency means that after an update, all replicas will eventually receive it and be consistent, but in the short term, different nodes may return slightly different values.

What is 'transparent data encryption' (TDE) in databases?

Answer: Encrypting the entire database storage files at rest so data is protected if storage media is stolen

TDE encrypts database storage files at rest, protecting data if physical storage media is stolen or accessed without authorization, transparently to applications.

What is the difference between a clustered and non-clustered index in SQL databases?

Answer: A clustered index determines the physical sort order of table rows; a non-clustered index is a separate structure pointing to data rows

A clustered index determines the physical order rows are stored in the table (only one per table), while non-clustered indexes are separate lookup structures pointing back to the data rows.

What is 'principle of least privilege' in database access control?

Answer: Granting users only the minimum permissions required to perform their job functions

The principle of least privilege grants each user or process only the minimum database permissions necessary for their legitimate work, limiting the damage from errors or attacks.