Scaling Writes easy
You add 5 new indexes to a table to speed up Reads. How does this affect Write performance (Insert/Update)?
- A Writes become faster.
- B Writes are unaffected.
- C Writes fail more often.
- D Writes become slower because the database must update the main table AND all 5 indexes for every change.
Answer: D. Writes become slower because the database must update the main table AND all 5 indexes for every change.
There is no free lunch. Indexes speed up lookups (Reads) but add overhead to modification (Writes). Every INSERT now requires writing to 6 places (1 Table + 5 Indexes).
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