Hi all,

I am having a little trouble getting my head round designing some tables as my links seem to be 1 to 1 for the most part.

I am designing a database to store items. The problem arises when it comes to storing unique data about different items, which would require new link to a table. Each item has an ItemID, however the types of items may vary from films, to music, etc. Each has its own attributes. Films would include platform (eg. DVD), music would include platform (eg. Record), etc. However, then a Record would need a table to store its size etc. Here is what I've got so far:

StockTable
ItemID
QuantityInStock
IndividualPrice
ItemTypeID

ItemTypeTable
ItemTypeID
ItemType (eg. Music)
TypeID

MusicTable
TypeID
Type (eg. Record)
RecordID (but what if it's a CD? It would need a MusicID)

RecordTable
RecordID
Size

It is creating that link between the ItemTypeTable, MusicTable, and the RecordTable that is causing me the most grief.

Could anyone help me figure out how to relate these items together in a relational database? Any help is appreciated