I really like this SQL. Clear question and expected output. I honestly don't think I can make it without continously comparing my answer to the expected outcome to further understand the requirement. Super!

I have the same problem. The year, month and day are not treated as separate columns.

This is a good kata. I have looked up stack overflow regarding crosstab and most of them use pivot or case. I find one finally 3002499 (search that in stack overflow) is about crosstab but they create a table and insert the value before have it crosstab. I am hoping to improve my problem solving skills. I got frustrated with creating a table first and do group by and order by as I need to combine all my new knowledge together. I cannot solve without understanding each function clearly. You have to understand each function clearly before you do you test and trial. Dont get discouraged when the return is not showing. Later I understand how crosstab works and I have used the information from the table I have created. By reading the information provided in the instruction does not help me to understand what crosstab mean as there is no clear specific example.

This kata can let you understand different functions of sql, research a new function if you have not heard and how you combine and test your understanding of each function to generate a desired result. Thank you.