In some cases, two transactions may, in the course of their processing, attempt to access the same portion of a database at the same time, in a way that prevents them from proceeding. Which of the following best describes this type of situation?

Which of the following best describes what transaction-processing system provides?

Which of the following best describes an operation that allows changes to adatabase to be available to all applications and users?

Josh has figured out that software glitches and power fluctuations that caused systems to go off line has resulted in incorrect data being saved into the company database. What does Josh need to make sure is configured so that this type of activity does not continue?

Database software performs three main types of integrity services: semantic,referential, and entity. Which of the following correctly describes one of these services?

i.A semantic integrity mechanism makes sure structural and semantic rules are enforced.
ii. A database has referential integrity if all foreign keys reference existing primary keys.
iii. Entity integrity guarantees that the tuples are uniquely identified by primary key values.

What needs to be put into place to ensure that two users cannot access and modify the same data within a databaase at the same time?

Lance needs to setup a relationship between two tables in the relational database he is working in. Which of the following best describes what does Lance need to create?

Matches between __________ and __________ are important because they represent references from one relation to another.

Which of the following identifies a row within a relational database and is used for indexing?

Which of the following has the advantages of ease of reusing code and reduced maintenance?