mysql按年份分组与按年份和月份分组

Question

I am trying to make some reports regarding our orders and the products sold, revenue and the total weight, but when im grouping our orders together I get different results in some of my queries that should return the same.

The following is my queries:

Monthly

SELECT
    MONTH(orders.date_purchased) as date,
    YEAR(orders.date_purchased) as year,
    count(DISTINCT orders.orders_id) AS total_orders,
    categories.fields_23 as currency
FROM
orders_shipping_products
Inner Join orders ON orders.orders_id = orders_shipping_products.orders_id
Inner Join categories ON categories.fields_6 = orders.shopping_store_category_id
WHERE
orders.orders_status NOT IN (0, 1, 99)
GROUP BY
date,
year,
categories.fields_23
ORDER by
    YEAR(orders.date_purchased),
    MONTH(orders.date_purchased) ASC,
    categories.fields_23

This returns for 2012 the following table, a total of 353:

+------+------+--------------+----------+
| date | year | total_orders | currency |
+------+------+--------------+----------+
|   11 | 2012 |           86 | EUR      |
|   12 | 2012 |          267 | EUR      |
+------+------+--------------+----------+

Yearly

SELECT
    YEAR(orders.date_purchased) as year,
    count(DISTINCT orders.orders_id) AS total_orders,
    categories.fields_23 as currency
FROM
orders_shipping_products
Inner Join orders ON orders.orders_id = orders_shipping_products.orders_id
Inner Join categories ON categories.fields_6 = orders.shopping_store_category_id
WHERE
orders.orders_status NOT IN (0, 1, 99)
GROUP BY
year,
categories.fields_23
ORDER by
    YEAR(orders.date_purchased),
    categories.fields_23

it returns for 2012 the following

+------+--------------+----------+
| year | total_orders | currency |
+------+--------------+----------+
| 2012 |          351 | EUR      |
+------+--------------+----------+

The only thing that changes is the total_orders, total amount of products, the revenue and weight is the same. I just get two more orders when checking per month. I also checked with a selection and grouping by QUARTER, YEAR that returns the following:

+---------+------+--------------+----------+
| quarter | year | total_orders | currency |
+---------+------+--------------+----------+
|       4 | 2012 |          351 | EUR      |
+---------+------+--------------+----------+

This make me thinks, that i might be doing something wrong with my selections when i want to generate a report per month

WITH ROLLUP

Daniel asked me to try add WITH ROLLUP on my query, follow is what i did and got in return

SELECT
    MONTH(orders.date_purchased) as date,
    YEAR(orders.date_purchased) as year,
    count(DISTINCT orders.orders_id) AS total_orders,
    categories.fields_23 as currency
FROM
orders_shipping_products
Inner Join orders ON orders.orders_id = orders_shipping_products.orders_id
Inner Join categories ON categories.fields_6 = orders.shopping_store_category_id
WHERE
orders.orders_status NOT IN (0, 1, 99)
GROUP BY
year,
date,
categories.fields_23 WITH ROLLUP

This is the returned data:

+------+------+--------------+----------+
| date | year | total_orders | currency |
+------+------+--------------+----------+
| 11   | 2012 |           86 | EUR      |
| 11   | 2012 |           86 | NULL     |
| 12   | 2012 |          267 | EUR      |
| 12   | 2012 |          267 | NULL     |
| NULL | 2012 |          351 | NULL     |
+------+------+--------------+----------+

Answer 1

I rechecked orders_id and it where not unique, in fact there where 2-3 the same orders id and some of them where located in different months. Found that a combination of orders_id and another column made it up for the real unique id. adding this to my join, solved everything.