Question

What is technical debt ratio in sonarqube?

Answer 1

SQALE is a methodology that was developed by inspearit and then open sourced. If you read the documentation at sqale.org, you'll see that it's about "organising the non-functional requirements that relate to the code’s quality." In the SonarQube implementation of the SQALE method, those non-functional requirements are the coding rules in your quality profile