You work for music company. The artists book time in our recording studios and we record each song that they perform as a track. We then work with the artist to group the tracks of their choosing into a collection, which would be a CD. Then we sell the CDs. Create an ERD for our new DBMS that we are planning to implement.

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Following are the business rules:

- Our CUSTOMERs consist of individuals that want to order copies of a CD we have produced. It doesnt matter who they are they could be local pubs interested in hearing bands for gigs, or it could be the artists, themselves, who want to restock demo items to distribute to market themselves. All that matters is that we have a CUSTOMER base that orders our CDs

- In our CUSTOMER table, we have only customers that have ordered from us already. If they have not ever ordered from us, they are not our customer yet.

- We refer to the CDs that we sell as an ITEM. Each CD is assigned a unique ITEM_NUM.

- Each customer places a SALES_ORDER with us.

- Each SALES_ORDER is comprised of at least one ITEM; however, there could be several items ordered by a CUSTOMER on a given SALES_ORDER just like any sales order on earth just like every other header/line pair weve gone over thus far.

- As already stated, we call our CDs, ITEMs.

- An ITEM is a collection of songs or TRACKs.

- Just like a CD that you may purchase today, you order the CD by the title of the CD, not the titles of any individual songs.

- Every STUDIO has produced at least one track. Otherwise stated, there is no STUDIO that has not produced a track

- Each STUDIO produces many TRACKs. Otherwise stated, many TRACKs are recorded at each STUDIO.

- However, a single TRACK cannot be recorded at multiple STUDIOs. A single TRACK can only be recorded in a single STUDIO (makes sense how do you stop a song mid-stream and go record the rest of it at another location?)

- Any TRACK can be included in multiple CD collections. Artists do this all of the time think about when they release a Best Hits CD that contains a bunch of songs from all different CDs they had released in the past.

- So, more specifically stated, many TRACKs can be included on many ITEMs.

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Be sure you have all PKs and FKs identified, relationship verbs, proper relationship line strengths set, and proper connectivities with only relationships that can be implemented (resolve M:N). All PKs should be numeric ID or NUM type attributes.