chinook/project_notes.md

Project Notes - SQL Interlude - Chinook

Questions

How to use NOT in queries

Why does

SELECT * FROM CUSTOMER
WHERE COUNTRY NOT LIKE 'USA';

work and

SELECT * FROM CUSTOMER
WHERE COUNTRY NOT 'USA';

does not work?

Answer

To avoid using LIKE

WHERE NOT customer.country = "USA";
or
WHERE NOT != "USA";

are valid ways of forming the query.

Resources

How to concatenate columns in SQL - CONCAT_WS()