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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?

Deze oefening maakt deel uit van de cursus

Introduction to Redshift

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