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Thursday, January 12, 2017

Codecademy SQL Table Transformation Subqueries Walkthrough


  • 1. Table Transformation
    • SELECT * FROM flights WHERE (SELECT code FROM airports WHERE elevation < 2000); 
    • Nested subqueries 
    • First get all the codes from airports table if its elevation is smaller than 2000
    • Use this as a filter to query all columns of data from the flights table
    • Don't forget the ; semicolon in the end

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