Question

I’m having a problem that I assume is related to the Join in my SQL statement.

select s.customer as 'Customer', 
    s.store as 'Store', 
    s.item as 'Item', 
    d.dlvry_dt as 'Delivery', 
    i.item_description as 'Description', 
    mj.major_class_description as 'Major Description', 
    s.last_physical_inventory_dt as 'Last Physical Date', 
    s.qty_physical as 'Physical Qty', 
    s.avg_unit_cost as 'Unit Cost', 
    [qty_physical]*[avg_unit_cost] as Value 
from argus.DELIVERY d 
join argus.STORE_INVENTORY s 
    ON (s.store = d.store)
join argus.ITEM_MASTER i 
    ON (s.item = i.item)
join argus.MINOR_ITEM_CLASS mi 
    ON (i.minor_item_class = mi.minor_item_class)
join argus.MAJOR_ITEM_CLASS mj 
    ON (mi.major_item_class = mj.major_item_class)
where s.last_physical_inventory_dt between '6/29/2011' and '7/2/2012' 
    and s.customer = '20001' 
    and s.last_physical_inventory_dt IS NOT NULL

It comes back with a seemingly infinite amount of copies of one record. Is there something wrong with the way I’m joining these tables?

Answer 1

join argus.MINOR_ITEM_CLASS mi 
    ON (i.minor_item_class = mi.minor_item_class)
join argus.MAJOR_ITEM_CLASS mj 
    ON (mi.major_item_class = mj.major_item_class)

My guess is that your error resides in one of these 2 joins. When you only use the word JOIN it assumes that you are trying to do an INNER JOIN which returns all records that have at least 1 to 1. I don’t know what your data looks like but I am assuming that there is a many to many relationship between minor item class and major item class so when you run this query you are receiving duplicated records for almost every field, but the major item class differs.

I would look at the results. Most of the columns will have repeating data that doesn’t change while one of the columns will have a different value for every row. That should tell you that the column with differing data for each row is the column that you should be joining differently.

Otherwise, I would say that your query is formatted correctly.