Join tables

Part of exploring a database is figuring out how tables relate to each other. The company and fortune500 tables don't have a formal relationship between them in the database, but this doesn't prevent you from joining them.

To join the tables, you need to find a column that they have in common where the values are consistent across the tables. Remember: just because two tables have a column with the same name, it doesn't mean those columns necessarily contain compatible data. If you find more than one pair of columns with similar data, you may need to try joining with each in turn to see if you get the same number of results.

Reference the entity relationship diagram if needed.

Deze oefening maakt deel uit van de cursus

Exploratory Data Analysis in SQL

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Oefeninstructies

Closely inspect the contents of the company and fortune500 tables to find a column present in both tables that can also be considered to uniquely identify each company.
Join the company and fortune500 tables with an INNER JOIN.

Praktische interactieve oefening

Probeer deze oefening eens door deze voorbeeldcode in te vullen.

SELECT company.name
-- Table(s) to select from
  FROM company
       INNER JOIN ___
       ___ ___.___=___.___;

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