Combining functions for string manipulation
In the next example, we are going to break apart the email column from the customer table into three new derived fields. Parsing a single column into multiple columns can be useful when you need to work with certain subsets of data. Email addresses have embedded information stored in them that can be parsed out to derive additional information about our data. For example, we can use the techniques we learned about in the video to determine how many of our customers use an email from a specific domain.
Este exercício faz parte do curso
Functions for Manipulating Data in PostgreSQL
Instruções do exercício
- Extract the characters to the left of the
@of theemailcolumn in thecustomertable and alias it asusername. - Now use
SUBSTRINGto extract the characters after the@of theemailcolumn and alias the new derived field asdomain.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
SELECT
-- Extract the characters to the left of the '@'
___(___, ___('@' IN email)-1) AS username,
-- Extract the characters to the right of the '@'
___(___ FROM ___('@' IN email)+1 ___ ___(___)) AS domain
FROM customer;