Question: What is the average number of years the respondents who are professional coders have been coding by developer type?
SQL:
SELECT DevType, AVG(YearsCodePro) FROM Responses WHERE NOT DevType IS NULL GROUP BY DevType
SELECT DevType, AVG(YearsCode) AS AverageYearsCoding FROM Responses WHERE ResponderDescription = 'I am a developer by profession' AND NOT YearsCode IS NULL GROUP BY DevType