Evaluating filter performance
The Idaho field office is reporting issues with a query they are using to get the average well depth for each latitude. One thing you decide to check is the effectiveness of the welldepthmeasure
WHERE
condition clause.
SELECT latitudemeasure, AVG(welldepthmeasure)
FROM public_intro_redshift.idaho_monitoring_location
WHERE welldepthmeasure > 0.00
GROUP BY latitudemeasure
ORDER BY latitudemeasure
Using the EXPLAIN
output of this query, how many rows were scanned after the where cause was applied?
This exercise is part of the course
Introduction to Redshift
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