Database Systems & SQL Flashcards
6 cards from real B.S.W.E. Bachelor of Software Engineering practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Database Systems & SQL flashcards as text
What does ACID stand for in database transactions?
Answer: Atomicity, Consistency, Isolation, Durability
ACID (Atomicity, Consistency, Isolation, Durability) defines the properties that guarantee database transactions are processed reliably.
Which SQL command removes a table and all its data permanently?
Answer: DROP
DROP TABLE removes the entire table structure along with all its data and the schema definition from the database.
What is a foreign key in a relational database?
Answer: A field referencing the primary key of another table
A foreign key is a column that establishes a referential link between two tables by pointing to the primary key of another table.
What type of JOIN returns all rows when there is a match in either table?
Answer: FULL OUTER JOIN
A FULL OUTER JOIN returns all rows from both tables, filling with NULL values where no match exists in either table.
What is normalization in database design?
Answer: Organizing data to reduce redundancy and improve integrity
Normalization organizes a database structure to reduce data redundancy and improve data integrity through a series of normal forms.
Which SQL aggregate function returns the number of rows matching a condition?
Answer: COUNT()
COUNT() returns the number of rows that match a specified condition or the total rows in a result set.