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Exercise

Partitioning on location

The air quality index (AQI) is calculated on four air pollutants (ozone, particle pollution, carbon monoxide, and sulfur dioxide) then categorized into six levels.

Air quality in the US is monitored on a state level, with states reporting data to the Environmental Protection Agency (EPA). Because of these different sources, the air quality table is partitioned by state. While it looks like one table, each state has its own child table.

Find the cost estimate impact of the partition. Then find the best days and places to visit in Hawaii based on the AQI.

Instructions 1/3

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  • 1

    Filter to Hawaii (state_code = 15) and check the query cost estimate on an unpartitioned version of the table.

  • 2

    Check the query cost estimate on a partitioned version of the table.

  • 3

    Now use the partition on state_code to find the days with the best air quality in Hawaii (15).