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Discover how to calculate and compare the average ratings of the top touristic places across different countries in MySQL with a step-by-step guide.
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Comparing Average Ratings of the Top Touristic Places by Country Using MySQL

When it comes to traveling, ratings play a crucial role in guiding tourists toward the best destinations. If you're analyzing touristic spots and their ratings, you might find yourself wanting to compare the average ratings of the top touristic places in different countries. This can be particularly interesting when you want to showcase which country boasts the highest-rated attractions. In this post, we will tackle this specific problem using MySQL—a powerful database management system.

The Problem

Imagine you have a table containing three key fields:

Touristic Place: The name of the attraction.

Country: The country where the attraction is located.

Average Rating: The rating given by tourists for that place.

Here’s a simplified view of your data:

[[See Video to Reveal this Text or Code Snippet]]

You want to know how the average ratings of the top five touristic places in France compare with those in Croatia. Although you might already know how to average ratings for all places in a country, the challenge lies in using LIMIT in conjunction with GROUP BY to get only the top five rated places for each country.

The Solution

The key to solving this problem is to use window functions, particularly if you are using MySQL 8.0 or later versions. Here's a structured way to formulate your SQL query for this requirement.

Step 1: Understanding Window Functions

Window functions allow you to perform a calculation across a set of table rows that are related to the current row. In our case, you can utilize the ROW_NUMBER() function to rank the ratings within each country.

Step 2: Writing the Query

To calculate the average rating of the top five touristic places for each country, you can use the following SQL query:

[[See Video to Reveal this Text or Code Snippet]]

Breakdown of the Query:

Inner Query: This part of the query assigns a rank (using ROW_NUMBER()) to each rating per country based on the rating in descending order.

Filtering: We only select entries (WHERE rn <= 5) that are among the top five rated attractions in each country.

Aggregation: Finally, we group the results by country and calculate the average rating (AVG(rating)) for these top-rated places.

Step 3: Running the Query

After crafting your query, run it using your MySQL environment. You will get results that show the average ratings of the top five attractions in each specified country, allowing for easy comparison.

Conclusion

By utilizing window functions and carefully structuring your SQL queries, you can derive insightful comparisons of average ratings of touristic spots across various countries. This method not only streamlines the process but also enhances your ability to analyze data effectively.

Now that you have the knowledge and the query at your disposal, you can delve deeper into the fascinating world of travel ratings and gain valuable insights into which countries offer tourists the most impressive experiences.

Happy querying!