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Staffelter Hof Winery is Germany's oldest business, established in 862 under the Carolingian dynasty. It has continued to serve customers through dramatic changes in Europe, such as the Holy Roman Empire, the Ottoman Empire, and both world wars. What characteristics enable a business to stand the test of time?
To help answer this question, BusinessFinancing.co.uk researched the oldest company still in business in almost every country and compiled the results into several CSV files. This dataset has been cleaned.
Having useful information in different files is a common problem. While it's better to keep different types of data separate for data storage, you'll want all the data in one place for analysis. You'll use joining and data manipulation to work with this data and better understand the world's oldest businesses.
The Data
businesses and new_businesses
| Column | Description |
|---|---|
business | Name of the business (varchar) |
year_founded | Year the business was founded (int) |
category_code | Code for the business category (varchar) |
country_code | ISO 3166-1 three-letter country code (char) |
countries
| Column | Description |
|---|---|
country_code | ISO 3166-1 three-letter country code (varchar) |
country | Name of the country (varchar) |
continent | Name of the continent the country exists in (varchar) |
categories
| Column | Description |
|---|---|
category_code | Code for the business category (varchar) |
category | Description of the business category (varchar) |
-- What is the oldest business on each continent?
-- CTE for oldest business by continent
WITH c1 AS(
SELECT b.country_code, countries.continent, countries.country, b.year_founded, ROW_NUMBER () OVER(PARTITION BY countries.continent
ORDER BY year_founded) AS old_rank
FROM businesses AS b
INNER JOIN countries
ON countries.country_code = b.country_code)
SELECT c1.continent, c1.country, b1.business, c1.year_founded
FROM c1
INNER JOIN businesses AS b1
ON b1.country_code = c1.country_code
WHERE c1.old_rank = 1
-- How many countries per continent lack data on the oldest businesses
-- Does including the `new_businesses` data change this?
WITH cte AS(
SELECT countries.*, b.* --combine both tables
FROM (SELECT * --business & new business
FROM businesses
UNION ALL
SELECT *
FROM new_businesses) AS b
RIGHT JOIN countries --keeps null values
ON b.country_code = countries.country_code
WHERE b.business IS NULL) --filter for NULL values
SELECT cte.continent, COUNT(cte.*) AS countries_without_businesses --Main query
FROM cte
GROUP BY continent;
-- Which business categories are best suited to last over the course of centuries?
WITH cte AS(
SELECT co.continent, ca.category, b.year_founded, ROW_NUMBER() OVER (PARTITION BY co.continent, ca.category ORDER
BY b.year_founded) AS old_rank
FROM businesses AS b
INNER JOIN countries AS co
ON b.country_code = co.country_code
INNER JOIN categories AS ca
ON b.category_code = ca.category_code)
SELECT continent, category, year_founded
FROM cte
WHERE old_rank = 1;