Exercise

Identifying duplication

Duplication can happen for a number of reasons, often in unexpected ways. Because of this, it's important to get in the habit of validating your queries to ensure no duplication exists. To validate a query, take the following steps:

Check the total value of a metric from the original table.
Compare that with the total value of the same metric in your final report.

If the number from step 2 is larger than step 1, then duplication is likely the culprit. In this exercise, you will go through these steps to identify if duplication exists.

Instructions 1/3

XP

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Setup a query that pulls total gold_medals from the winter_games table.

Take Hint (-10 XP)