snowflake cloud data platform - Is there a function in SQL that automatically generates more rows by month?

Question

I've got a large database that's got all our transactions and shipping costs from them, here's a simplified version:

Source Table

Date	ROUTE	Cost
01/20/21	USA to UK	$40
01/01/21	USA to UK	$40
01/10/21	USA to UK	$40
12/20/20	USA to UK	$30
11/20/20	USA to UK	$20
11/20/20	USA to UK	$20

question from:https://stackoverflow.com/questions/65946864/is-there-a-function-in-sql-that-automatically-generates-more-rows-by-month

Answer 1

Here is a possible way of doing it by using PIVOT in Snowflake: https://docs.snowflake.com/en/sql-reference/constructs/pivot.html

Let's say "monthname" is a column you extracted out of your "Date"-column, probably this helps:

select * from yourTable
pivot(sum(cost) for monthname in ('January', 'February', 'March', 'April'))
order by route;

The values of your monthname-column should match the one in the brackets.

As this is a more static solution, you still have to adjust the code every month. Here probably writing a stored procedure is helping: https://docs.snowflake.com/en/sql-reference/stored-procedures.html