To begin, we need something to normalize. Through this section we will create a database to keep track of a music collection. First, we need a list of what we want to track. We will follow what is generally useful for a collection of music, like albums, artists, and songs. These categories give us a list of things we want to store, so let us come up with what a full record might contain:
Bryan Adams So Far So Good Full Album Zip
(reference to Album)We can already see a thread weaving its way through our tables. Even though these fields are no longer all in one record together, you can see how we can trace our way through by looking for the band we want in the albums table, and when we know the albums, we can find all the tracks the band has published. To continue with our design we will move to song length. This field sounds fitting in our songs table, and is only one piece of information, so we are off to a good start! We can also see that we would only have one song length per record as each record here is a song, so we comply with column count, too. We can put it there for now, and will see if it meets the rest of our tests as we move on.
DateNow that we have exhausted our initial list, we will consider the last element of 1NF, which is primary keys for each table. Many of our tables are not presenting us with good candidates, as band names, venues, albums, tracks, and even artists could share the same names as time goes on. To make things consistent, we will create auto incrementing IDs for each table. To follow best practices, we will use the singular version of the noun with ID after it to denote our primary keys. This identifies the row as a singular version of the concept our table name is a plural of: 2ff7e9595c
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