Detecting invalid values with regular expressions
In the video exercise, we saw that there are a number of ways to detect invalid values in our data. In this exercise, we will use regular expressions to identify records with invalid values in the parking_violation table.
A couple of regular expression patterns that will be useful in this exercise are c{n} and c+. c{n} matches strings which contain the character c repeated n times. For example, x{4} would match the pattern xxxx. c+ matches strings which contain the character c repeated one or more times. This pattern would match strings including xxxx as well as x and xx.
Cet exercice fait partie du cours
Cleaning Data in PostgreSQL Databases
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
SELECT
summons_number,
plate_id,
registration_state
FROM
parking_violation
WHERE
-- Define the pattern to use for matching
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