Scaling Reads easy
What is the primary function of a Database Index?
- A To reduce the time it takes to find specific rows (Lookup speed).
- B To compress the data size on disk.
- C To encrypt the data.
- D To automatically backup the table.
Answer: A. To reduce the time it takes to find specific rows (Lookup speed).
An index acts like the table of contents in a book. Instead of scanning every page (Full Table Scan) to find 'Chapter 5', the database looks up the page number in the index and jumps directly there.
One system design question a day, with spaced repetition so the ones you miss come back.
Get the appRelated questions
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- What is the main downside of reading from a Read Replica instead of the Primary database?
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- You have 5 Read Replicas. How does the application know which one to ask for data?