database - What type of entity is this? -
So I'm trying to get it into 3 NF. is this correct? If so, what do you call this unit?
If I have details in the table It would depend on donut name, so I had to put it in 3 NF and take it to my desk. correct?
Thank you for any help, just to make sure I am on the right track. :)
* Edit
Example of Data:
I think your data is
name details Unit Pays
Based on your description, a basic assumption: Name is a candidate key, no two donuts will have the same name
If the details are also unique within the table, then it is also a candidate key. If it is not unique, So this is just one feature, similar to the unitpiece (i.e. the table can have the same value in two rows).
When you have two candidate keys, you choose one and make it Primary key , and all other Optional keys This does not violate the third common form.
Next impression: DonutId is an identity column - or , Any other device that remembers one (essentially) in each line Specifies the integer integer value it creates a key of the key - it is unique, it can work as a candidate key (and "promoted" to the primary key), but the data There is no intrinsic significance or meaning (for example donut # 37 donuts have no meaning for the world) it will give you three candidate keys, soon after the primary key and two optional keys, It looks like the third normal form (the other column will be Natural Key .)
So far, as far as educationists are concerned, I can be wrong - all of these Candidates may need further further down the BCNF, the fourth general form, the fifth general form, and whatnot ... but considering the overall simplicity of the data, I do not think so.
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