mysql group by year diffrent from group by year and month - mysql

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.