Boost Your Database: Easy Interview Questions on Performance Improvement Quiz

1. Understanding Indexes

   Which of the following is most effective for speeding up searches in a large table with millions of rows, such as finding a user by email address?

   1. A. Creating an index on the email address column
   2. B. Increasing the size of the table
   3. C. Duplicating rows in the table
   4. D. Adding more columns to the table
   5. E. Using uppercase letters in column names

2. Optimizing Queries

   You notice that a query selecting all columns from a table runs slowly. Which optimization could quickly improve its performance?

   1. A. Selecting only the needed columns instead of all columns
   2. B. Deleting random rows
   3. C. Changing data types to larger ones
   4. D. Sorting the table alphabetically in every query
   5. E. Using more joins than necessary

3. Normalization Basics

   Why does removing repetitive data (for example, customer addresses repeated in every order) help improve database performance?

   1. A. It reduces data redundancy and increases efficiency
   2. B. It adds more storage to the table
   3. C. It complicates queries unnecessarily
   4. D. It slows down backup processes
   5. E. It requires larger network cables

4. Writing Efficient Queries

   Given a choice, which sorting operation is faster and less resource-intensive for a database?

   1. A. Sorting by an indexed column
   2. B. Sorting by a calculated field every time
   3. C. Sorting by unrelated tables
   4. D. Sorting by all columns at once
   5. E. Sorting by misspelled column names

5. Caching Strategies

   How does enabling query result caching benefit a frequently accessed, rarely changing 'product list' table?

   1. A. It reduces the need to run the same query repeatedly
   2. B. It increases the number of rows in the table
   3. C. It causes outdated results to display forever
   4. D. It slows down users from accessing the table
   5. E. It prevents any future updates to the table