MySQL select using row counts and grouping - mysql

Question

I have 2 tables, orders and order_lineitems.
orders contains the order status info (sold date, invoice no, type of sale, etc)
order_lineitems contains the item(s) for each order in a one to many relationship.
Since we provide shipping info by line item, ship_date is in the order_lineitems table, null if not shipped, a date if it is shipped.
I am trying to pull the orders where all items have shipped by comparing the number of line item rows against the line item rows that have a ship date. While I have successfully pulled all that info, I am unable to make the last step, limiting the result set to include only the completely shipped orders (number of rows = number of rows where ship_date is not null).
I know I am missing something simple, but just don't see it..
select sum(custom.lineitems) as totalitems, sum(custom.shipped) as totalshipped,
custom.invoice, z.shipregion
from (
select a.invoice, count(a.invoice) as lineitems, 0 as shipped
from order_lineitem a
group by a.invoice
UNION ALL
select b.invoice, 0 as notshipped, count(b.ship_date) as shipped
from order_lineitem b
where b.ship_date is not null
group by b.invoice
) as custom
left join orders z on custom.invoice = z.invoice
where z.result = 0
and z.respmsg like 'Approved%'
and z.shipregion <> 'PENDING'
and z.cancelorder = 0
group by custom.invoice;
This returns a result set like so (one row for each invoice in the DB)
totalitems totalshipped invoice shipregion
4 2 1000 REGION08
1 1 10001 REGION07
1 1 10004 REGION05
3 1 10006 REGION05
2 2 10007 REGION04
1 1 10008 REGION08
7 7 10009 REGION01
1 1 1001 REGION08
What I am looking for is a result set like this - only where totalitems = totalshipped
totalitems totalshipped invoice shipregion
1 1 10001 REGION07
1 1 10004 REGION05
2 2 10007 REGION04
1 1 10008 REGION08
7 7 10009 REGION01
1 1 1001 REGION08

Answer 1

Use HAVING clause
SELECT a.invoice, z.shipregion, COUNT(a.invoice) AS lineitems,
SUM(CASE WHEN a.ship_date IS NOT NULL THEN 1 ELSE 0 END) AS shipped
FROM order_lineitem a
LEFT JOIN orders z ON a.invoice = z.invoice AND z.result = 0 AND z.cancelorder = 0 AND
z.respmsg LIKE 'Approved%' AND z.shipregion <> 'PENDING'
GROUP BY a.invoice HAVING lineitems = shipped
OR
SELECT a.invoice, a.shipregion, a.lineitems, a.shipped
FROM (SELECT a.invoice, z.shipregion, COUNT(a.invoice) AS lineitems,
SUM(CASE WHEN a.ship_date IS NOT NULL THEN 1 ELSE 0 END) AS shipped
FROM order_lineitem a
LEFT JOIN orders z ON a.invoice = z.invoice AND z.result = 0 AND z.cancelorder = 0 AND
z.respmsg LIKE 'Approved%' AND z.shipregion <> 'PENDING'
GROUP BY a.invoice
) AS a WHERE a.lineitems = a.shipped

Answer 2

One more outer query needed.
select * from
(
\\Your whole query here
) as Result
where Result.totalitems = Result.totalshipped