From the course: Learning Relational Databases

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Second normal form

Second normal form

From the course: Learning Relational Databases

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Second normal form

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- Second Normal Form or 2NF might be a relatively easy gate to pass, depending on how you set up your primary keys. If all of your tables use only a single field or column as their primary key then congratulations you've already passed the requirements of 2NF. If you're using a composite primary key though, that's to say a primary key that requires two or more fields than conjunction to uniquely identify a record then we do have a little bit more work to do here. A table is in Second Normal Form if all the fields in the primary key are required to determine the other non-key fields. Here's an example. Here I have a table that is keeping track of the individual LineItems for an invoice. But it has a slightly different configuration than the one that we previously see. Here the Invoice Number and a Product Name are composite keys that link to a specific order that was placed and the specific item that was ordered. The reason the composite key was chosen in this table was so that we're…

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