SQL for Java Devs · interview question
How does an index on a column speed up a sequential scan?
Multiple choiceHardchapter-8-curatedpremiumsql-for-java-devsindexes
Answer and explanation
Correct answer
C. Indexes allow the database to quickly locate the position of rows without scanning each one.
Why
Indexes use data structures that improve lookup time, allowing the database to find rows much faster by avoiding a full table scan. This reduces the number of data pages that need to be read.
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