![]() Note: Like with Kotlin classes, the convention is to use the singular form for the name of database tables. The presence of a foreign key means there's a relationship between the tables. When a table references the primary key of another table, it is known as a foreign key. This identifier is known as the primary key. For example, a graduate student might have a single professor as a doctoral advisor whereas that professor is the doctoral advisor for multiple students.Įvery table in a relational database contains a unique identifier for rows, such as a column where the value in each row is an automatically incremented integer. A database is called a relational database when it can model relationships between tables. Just as a spreadsheet can contain multiple sheets and an app can contain multiple classes, a database can contain multiple tables. Objects contain values for each property defined in the class, just as rows contain values for each column defined in the data table. Objects, like rows, are the actual data.Properties, like columns, define the specific pieces of data that every instance of the class should contain.Classes, like tables, model the data you want to represent in your app.The structure of a relational database also mirrors what you already know about classes and objects in Kotlin. ![]() Rows contain the actual data that consist of values for each column in the table. ![]()
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