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

You're not returning the totals. For example, instead of

product_name | year | month | day | total
-------------+------+-------+-----+------
 milk        | 2019 | 01    | 01  | 200
 milk        | 2019 | 01    |     | 200
 milk        | 2019 |       |     | 200
 milk        |      |       |     | 200

you only return

product_name | year | month | day | total
-------------+------+-------+-----+------
 milk        | 2019 | 01    | 01  | 200

There's a certain language feature which lets you easily generate these.

But Postgre 9.6 documentation says: logarithm to base 64 is [edited out]

It doesn't.

Please mark your post as having spoiler content next time. You have the arguments of your second method flipped.

To be more precise, can you poste in git flavored markdown, tell me the language and the specific test you are mentioning?

Mh, probably no.