From the course: Relational Databases Essential Training

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One-to-many relationships

One-to-many relationships

From the course: Relational Databases Essential Training

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One-to-many relationships

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- [Instructor] In a relational database, there are three different kinds of relationships that can be made between two tables. The most common, by a large margin, is a one-to-many relationship. If you think about your own life you'll easily find one-to-many relationships all around. Your one library card has been used to check out many books. Your one bank account has had many transactions. One-to-many relationships are everywhere. A one-to-many relationship doesn't mean that there is absolutely multiple related records though. It simply means that the database is configured to support the possibility. The relationship describes the tables not the data. Consider my library card, number 5005. In the beginning, I just opened the account and haven't checked out any books yet. The account is created in the Library Patron table but there are no matching records in the Book Loans table. Bu the relationship between the two tables…

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