DBMS slip test 1

What is the purpose of SQL query optimization?

• To reduce the amount of data stored in the database.

• To increase the complexity of SQL queries.

• To ensure data integrity during transactions.

• To improve the performance of SQL queries.

Which of the following is a common technique for optimizing SQL queries?

• Using stored procedures

• Using subqueries

• Using indexing

• Using temporary tables

What does ACID stand for in transaction management?

• Assurance, Consistency, Isolation, Durability

• Atomicity, Consistency, Isolation, Transferability

• Accuracy, Clarity, Integrity, Transparency

• Atomicity, Consistency, Isolation, Durability

How can indexing improve SQL query performance?

• Indexing slows down data retrieval by increasing the amount of data scanned during queries.

• Indexing has no effect on SQL query performance whatsoever.

• Indexing allows faster data retrieval by reducing the amount of data scanned during queries.

• Indexing only improves performance for read operations, not for write operations.

Which SQL command is used to start a transaction?

• INITIATE TRANSACTION

• START TRANSACTION

• BEGIN TRANSACTION

• OPEN TRANSACTION

What is the difference between a committed and a rolled-back transaction?

• A committed transaction is temporary, while a rolled-back transaction is permanent.

• A committed transaction undoes changes, while a rolled-back transaction saves changes.

• A committed transaction saves changes, while a rolled-back transaction undoes changes.

• A committed transaction is only for read operations, while a rolled-back transaction is for write operations.

What is the role of a primary key in a database table?

• To uniquely identify each record in a table.

• To allow duplicate records in a table.

• To create relationships between tables.

• To store large amounts of data.

Which SQL clause is used to filter records in a query?

• ORDER BY

• GROUP BY

• WHERE

• HAVING

What is the purpose of a foreign key in a database?

• To uniquely identify each record in a table.

• To create relationships between tables.

• To store large amounts of data.

• To allow duplicate records in a table.

What is a stored procedure in SQL?

• A set of SQL statements that can be stored and reused.

• A command to delete records from a table.

• A method to create indexes on a table.

• A way to optimize SQL queries automatically.