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) |
Do some quick data quality checks and EDA
-- Data quality checks
-- table categories
select
count(*) as records_cnt,
count(category_code) as category_code_cnt,
count(category) as category_cnt
from categories;-- Data quality checks
-- table categories
select
count(*) as records_cnt,
count(country_code) as category_code_cnt,
count(country) as category_cnt,
count(continent) as continent_cnt
from countries;-- Data quality checks
-- table categories
select
count(*) as records_cnt,
count(business) as category_code_cnt,
count(year_founded) as category_cnt,
count(category_code) as continent_cnt,
count(country_code) as country_cnt
from public.businesses;-- Data quality checks
-- table categories
select
count(*) as records_cnt,
count(business) as category_code_cnt,
count(year_founded) as category_cnt,
count(category_code) as continent_cnt,
count(country_code) as country_cnt
from public.new_businesses;-- What is the oldest business on each continent?
WITH united_business AS (
SELECT *
FROM public.businesses
UNION
SELECT *
FROM public.new_businesses ),
prep_table AS (
SELECT
continent, country, business, year_founded,
ROW_NUMBER() OVER(PARTITION BY continent ORDER BY year_founded ASC) as row_number
FROM united_business as bu
LEFT JOIN countries as co USING(country_code)
LEFT JOIN public.categories as ca USING(category_code)
ORDER BY continent ASC, row_number ASC)
SELECT continent, country, business, year_founded
FROM prep_table
WHERE row_number = 1;-- How many countries per continent lack data on the oldest businesses
-- Does including the `new_businesses` data change this?
SELECT
c.continent,
count(c.country_code) AS countries_without_businesses
FROM
(SELECT *
FROM public.businesses
UNION
SELECT *
FROM public.new_businesses
) as b
RIGHT JOIN public.countries as c ON c.country_code = b.country_code
WHERE b.country_code IS NULL
GROUP BY c.continent
;
-- Which business categories are best suited to last over the course of centuries?
SELECT
continent,
category,
MIN(year_founded) as year_founded
FROM businesses as bu
INNER JOIN countries as co USING(country_code)
INNER JOIN public.categories as ca USING(category_code)
GROUP BY continent, category
ORDER BY continent, category
;