Free Test Views, Indexes, and Co... – Databas...

Q1: What is a view in SQL?

A. A virtual table based on a SELECT query B. A physical table C. A type of index D. A backup table

Q2: Which command creates a view?

A. CREATE VIEW view_name AS SELECT ... B. CREATE TABLE view_name C. CREATE INDEX view_name D. CREATE VIRTUAL TABLE view_name

Q3: What is an index in a database?

A. A data structure to improve query speed B. A type of view C. A backup of the table D. A constraint on data

Q4: Which SQL command creates an index?

A. CREATE INDEX index_name ON table_name(column_name) B. CREATE TABLE index_name C. CREATE VIEW index_name D. CREATE CONSTRAINT index_name

Q5: Which of the following is a type of index?

A. B-tree B. Hash C. Bitmap D. All of the above

Q6: What is a PRIMARY KEY constraint?

A. Uniquely identifies each row B. Allows duplicate values C. Allows NULLs D. Links two tables

Q7: Which constraint prevents duplicate values?

A. UNIQUE B. NOT NULL C. CHECK D. FOREIGN KEY

Q8: Which constraint ensures a column cannot have NULL values?

A. NOT NULL B. UNIQUE C. PRIMARY KEY D. CHECK

Q9: What is a FOREIGN KEY constraint?

A. A key linking to a PRIMARY KEY in another table B. A key that uniquely identifies rows C. A constraint on column format D. An index

Q10: Which command removes a view?

A. DROP VIEW view_name B. DROP TABLE view_name C. DROP INDEX view_name D. DROP CONSTRAINT view_name

Q11: Can views be updated?

A. Sometimes, depends on the view B. Never C. Always D. Only if indexed

Q12: Which index type is best for exact match queries?

A. Hash index B. B-tree index C. Bitmap index D. Full-text index

Q13: What does the CHECK constraint do?

A. Enforces a condition on values B. Prevents NULLs C. Prevents duplicates D. Links tables

Q14: Which constraint is automatically created with PRIMARY KEY?

A. UNIQUE B. NOT NULL C. CHECK D. FOREIGN KEY

Q15: Which SQL clause is used to enforce constraints?

A. CONSTRAINT B. WHERE C. GROUP BY D. ORDER BY

Q16: What is a clustered index?

A. An index that determines physical order of data B. An index on a single column C. An index that is non-unique D. An index created on a view

Q17: Which index type is efficient for low cardinality columns?

A. Bitmap index B. B-tree index C. Hash index D. Full-text index

Q18: Which statement about views is TRUE?

A. Views do not store data physically B. Views store data physically C. Views improve insert performance D. Views create indexes

Q19: Which constraint enforces referential integrity?

A. FOREIGN KEY B. PRIMARY KEY C. UNIQUE D. CHECK

Quiz for Views, Indexes, and Constraints