True or False: The foreign_key must reference a dimension name, not a column name.

True or False: The foreign_key must reference a dimension name, not a column name.

• A. True
• B. False
• C. It can reference either
• D. Only under certain conditions

Answer: (A)

The statement is true because in Looker, when defining a foreign key in a join, it must reference a dimension within the model rather than a specific column in the underlying database table. Essentially, a dimension corresponds to a defined field in the LookML model, which allows Looker to abstract the database schema and provide a more user-friendly way to interact with data. Referencing dimensions allows Looker to interpret the database schema consistently across different tables and ensures that the relationships defined in LookML are clearer and more maintainable. This approach not only promotes proper data modeling practices but also allows Looker to leverage any transformations or calculations defined in those dimensions when executing queries. Consequently, specifying the foreign key to reference a dimension ensures that the connection between tables is based on the defined data model rather than relying on underlying database structures that may vary or change over time.

The statement is true because in Looker, when defining a foreign key in a join, it must reference a dimension within the model rather than a specific column in the underlying database table. Essentially, a dimension corresponds to a defined field in the LookML model, which allows Looker to abstract the database schema and provide a more user-friendly way to interact with data.

Referencing dimensions allows Looker to interpret the database schema consistently across different tables and ensures that the relationships defined in LookML are clearer and more maintainable. This approach not only promotes proper data modeling practices but also allows Looker to leverage any transformations or calculations defined in those dimensions when executing queries.

Consequently, specifying the foreign key to reference a dimension ensures that the connection between tables is based on the defined data model rather than relying on underlying database structures that may vary or change over time.