Question

I’m creating a php/mysql app and I’m trying to run a query based on a user supplied date, then using those results return the query if another date does not exist or match.

I have multiple orders that I want to query based on a few things, like so:

1. The user supplies a date.
   MySQL uses supplied date and returns the rows only if there are NO “Orders” that have a more present date associated to that Customer_ID. So I only want a value if there are NO newer orders based on the user supplied date.

Here’s what I’ve been playing with:

SELECT
o.Customer_ID, o.ShippingCompanyName, cg.Category, cd.Category_ID, o.Order_ID,

SUM(o.CustomerOrderTotal) as TOTAL,
COUNT(o.Order_ID) as ORDERS,
MAX(o.OrderPlaceServerTime) as LASTORDER

FROM Orders o

LEFT JOIN CustomerDetails cd ON o.Customer_ID = cd.Customer_ID
LEFT JOIN _CustomerCategory cg ON cg.Category_ID = cd.Category_ID

WHERE (
        o.OrderPlaceServerTime <= '".$BEFORE."'
    AND o.OrderPlaceServerTime NOT BETWEEN '".$BEFORE."' AND NOW()
      )

AND o.IsVOID = 0
AND o.IsPENDING = 0                     

GROUP BY o.Customer_ID
ORDER BY TOTAL DESC

I’m not getting the results I want. I gives me Customer Orders that also have newer orders than the user supplied date.

Also the “Dates” are like ‘2010-10-10 10:05:55’ so with data & time.

I’m a bit lost so I’m hoping someone can help me here or point me in the right direction.

Thanks.

Answer 1

You are mixing two things in the same query.

Each time the WHERE expressions run they check a SINGLE row! They do not check other rows. So when you check the dates you are basically saying WHERE i is less then 5 and i is not greater than 5. Which is pointless – you already said less then 5 in the first expression.

Change the WHERE to:

o.OrderPlaceServerTime <= '$BEFORE' AND
NOT EXISTS (SELECT * FROM Orders WHERE Orders = o.Customer_ID AND OrderPlaceServerTime > '$BEFORE')