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Fix typo 'nycfights13' to 'nycflights13' (#1575)

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Yvonne Fröhlich 2023-10-26 04:11:56 +02:00 committed by GitHub
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joins.qmd
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@ -42,7 +42,7 @@ You'll also learn how to check that your keys are valid, and what to do if your
Every join involves a pair of keys: a primary key and a foreign key. Every join involves a pair of keys: a primary key and a foreign key.
A **primary key** is a variable or set of variables that uniquely identifies each observation. A **primary key** is a variable or set of variables that uniquely identifies each observation.
When more than one variable is needed, the key is called a **compound key.** For example, in nycfights13: When more than one variable is needed, the key is called a **compound key.** For example, in nycflights13:
- `airlines` records two pieces of data about each airline: its carrier code and its full name. - `airlines` records two pieces of data about each airline: its carrier code and its full name.
You can identify an airline with its two letter carrier code, making `carrier` the primary key. You can identify an airline with its two letter carrier code, making `carrier` the primary key.