Index Scan vs Sequential Scan

Problem

An index is created on employee salaries, but running SELECT * FROM employees WHERE salary > 10 still performs a full table scan. The query planner determined it is faster to scan everything. Write a query that outputs reason with the value: "The query planner will bypass an index and perform a sequential scan if it estimates that a high percentage of rows match the filter."

Database Schema

This problem acts as a scratchpad. You will write your own DDL/DML or conceptual queries, so there is no predefined schema.

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Solution