Insert into a temp table
While you can join the results of multiple similar queries together with UNION, sometimes it's easier to break a query down into steps. You can do this by creating a temporary table and inserting rows into it.
Compute the correlations between each pair of profits, profits_change, and revenues_change from the Fortune 500 data.
The resulting temporary table should have the following structure:
| measure | profits | profits_change | revenues_change |
|---|---|---|---|
| profits | 1.00 | # | # |
| profits_change | # | 1.00 | # |
| revenues_change | # | # | 1.00 |
Recall the round() function to make the results more readable:
round(column_name::numeric, decimal_places)
Note that Steps 1 and 2 do not produce output. It is normal for the query result pane to say "Your query did not generate any results."
Questo esercizio fa parte del corso
Exploratory Data Analysis in SQL
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
DROP TABLE IF EXISTS correlations;
-- Create temp table
___ ___ ___ ___ AS
-- Select each correlation
SELECT 'profits'::varchar AS measure,
-- Compute correlations
___(___, ___) AS profits,
___(___, ___) AS profits_change,
___(___, ___) AS revenues_change
FROM ___;