From the course: SQL Server 2012: Designing Database Solutions
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Using first normal form - SQL Server Tutorial
From the course: SQL Server 2012: Designing Database Solutions
Using first normal form
- In this section, I'd like to talk about First Normal Form. First Normal Form states that the tables in our database will have no repeating columns. First let's look at an example that does have repeating columns, and we'll see why this can be a problem. Here is a hypothetical Orders table, for a database, and if we look at the data, we have customer John Doe placed an order for a Red Bicycle, Black Socks, and Red Shoes, all in one order. This database is designed to hold that data in three repeating columns. Those repeating columns being Item1, Item2, and Item3. For John Doe's order, because he ordered three items, this works perfectly fine. We have a little bit of a problem with Jane Smith. Jane Smith only ordered one item. Therefore, the column named Item2 and the column Item3 are going to be blank for her order, which is a little inefficient, but not too big of a problem. The biggest problem with this happens when a customer wants to order four items in the same order. There…
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