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Old January 24th, 2005, 06:01 PM
wstokarz
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Thank you for the replay.

Sorry for using generic terms like "pull data". I have taken 2 courses in MS
office when I was in college. Finding out that really did not help in my
situation.

I have treid the Junction Table path. I cannot use a primary key in the Item
table and the Layer table. I must be able to have many entries of the same
Work ID In both the Item Table and Layer Table as well as many items and
layers.

I am using Subforms within my parent form. Which work fine if I use primary
keys but limit me to only one Item, layer per Work ID.

The fourth table I ommited due to the fact i need to get this operational
first. The fourt table is a volume calculater based on the layer table.

Currently in my junction table I have Work ID, Item Num, LayerNum.

Thanks Bill

"Tim Ferguson" wrote:

"=?Utf-8?B?d3N0b2thcno=?=" wrote in
:


I'm trying to get a one to many relationship between four
tables.


No: you might want a one-to-many-to-many-to-many model though.

Each
table is embedded within the other.


No again: every table is pure independent and self contained on its own.
Just becuase MS's horrid "subdatasheets" make it look like something
else, don't let them fool you.

The process I wish to accomplish
is to have my primary table with the primary key pull data from
another table, the linked table will then pull data from another table
linked to it.


No yet again: Tables don't "pull" anything, ever. They only hold data, in
nice neat rows called records.

Basically The first table can have only one work
order, the next table can have many item numbers based on the work
order, the last table wil have many layer numbers based on both one
work order and the many item numbers.


I seem to have read something about this further up, but what you have
described _here_ is really simple:

WorkOrders(*WONumber, SizeOfJob, DateOrdered, etc)

Items(*WONumber+, *LineNumber, DesciptionOfItem, CostOfItem, Width)

Layers(*WONumber+, *LineNumber+, *LayerCode, Transparency, Thickness)


The (*) asterisks refer to primary keys: note that Items and Layers have
compound PKs made up of two or three fields. The (+) plusses refer to
foreigh keys: in other words, you can't have an Item that does not have a
valid WONumber; and you can't have a Layer that isn't attached to an Item
wit a real (WONumber, LineNumber) combination. Important note: there is
_no_ relationship directly enforced between Layers(WONumber) and
WorkOrders(WONumber).

Now, to see all the layers attached to each Item attached to each WO,
then it's easy to put them together in a query.

In a form, you could use a form-subform-subform arrangement, although
that gets messy for my taste.

If you are finding this hard, you might like to read some basic grounding
in R theory and database design. You will really need to understand this
stuff in order to get anything useful out of Access.

What happened to the fourth table?

Hope that helps


Tim F










I have tried junction tables and using primary keys. Neither have
worked
for me. Any ideas will be very helpful.



Thanks Bill