A basic pivot
You have the following table of Pole Vault gold medalist countries by gender in 2008 and 2012.
| Gender | Year | Country |
|--------|------|---------|
| Men | 2008 | AUS |
| Men | 2012 | FRA |
| Women | 2008 | RUS |
| Women | 2012 | USA |
Pivot it by Year to get the following reshaped, cleaner table.
| Gender | 2008 | 2012 |
|--------|------|------|
| Men | AUS | FRA |
| Women | RUS | USA |
Latihan ini adalah bagian dari kursus
PostgreSQL Summary Stats and Window Functions
Petunjuk latihan
- Create the correct extension.
- Fill in the column names of the pivoted table.
Latihan interaktif praktis
Cobalah latihan ini dengan menyelesaikan kode contoh berikut.
-- Create the correct extension to enable CROSSTAB
CREATE EXTENSION IF NOT EXISTS ___;
SELECT * FROM CROSSTAB($$
SELECT
Gender, Year, Country
FROM Summer_Medals
WHERE
Year IN (2008, 2012)
AND Medal = 'Gold'
AND Event = 'Pole Vault'
ORDER By Gender ASC, Year ASC;
-- Fill in the correct column names for the pivoted table
$$) AS ct (___ VARCHAR,
___ VARCHAR,
___ VARCHAR)
ORDER BY Gender ASC;