14. Quiz: Aliases for Multiple Window Functions

Shorten Your Window Function Queries by Aliasing

Window Function Alias

QUIZ QUESTION::

Using Derek's example in the previous window, deconstruct the window function alias into its two parts: the alias part and the window function part.

ANSWER CHOICES:



Part

Query text

Alias part

Window function part

SOLUTION:

Part

Query text

Alias part

Window function part

Now, create and use an alias to shorten the following query (which is different than the one in Derek's previous video) that has multiple window functions. Name the alias account_year_window, which is more descriptive than main_window in the example above.

SELECT id,
       account_id,
       DATE_TRUNC('year',occurred_at) AS year,
       DENSE_RANK() OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS dense_rank,
       total_amt_usd,
       SUM(total_amt_usd) OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS sum_total_amt_usd,
       COUNT(total_amt_usd) OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS count_total_amt_usd,
       AVG(total_amt_usd) OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS avg_total_amt_usd,
       MIN(total_amt_usd) OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS min_total_amt_usd,
       MAX(total_amt_usd) OVER (PARTITION BY account_id ORDER BY DATE_TRUNC('year',occurred_at)) AS max_total_amt_usd
FROM orders

Code

If you need a code on the https://github.com/udacity.