Unifying strings
Sometimes it's common to find messy strings when having different values for the same thing. Although all of these values can be valid, it is better to unify them to perform better analysis.
You run this query to filter all the airports located in the city of 'Chicago'
:
SELECT * FROM airports
WHERE airport_code IN ('ORD', 'MDW')
In the results, you see that there are inconsistent values for 'Chicago'
in the airport_city
column, with values such as 'ch'
. You will treat these inconsistent values by replacing them.
Cet exercice fait partie du cours
Cleaning Data in SQL Server Databases
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
SELECT
airport_code,
airport_name,
-- Use the appropriate function to unify the values
___(airport_city, '___', '___') AS airport_city,
airport_state
FROM airports
WHERE airport_code IN ('ORD', 'MDW')