Relational database design explained — sort of
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It helps ensure data consistency and integrity. This may not seem important at first. But it becomes critical when you want to query or sort that data.
For example, we have three books by Toni Morrison in the database. if we stored author information in the same table, every time someone wanted to add a Toni Morrison book, they would have to type "Toni Morrison" in the author field.
That's fine, as long as this person types well. But letters often get transposed, and some names are easy to misspell. If a user enters "Toni Morisson," that book title won't appear in a "Toni Morrison" search. We can help ensure data consistency with a separate authors table.