stack or union multiple fields in MS Access

Question

Beginner's question here... I have a table of tree measurements being 3 fields: - ID, Diameter_1, Diameter_2

& I wish to get to these 3 fields: - ID, DiameterName, DiameterMeasurement Input and Desired Output

SELECT DISTINCT ID, Diameter_1
FROM tblDiameters
UNION SELECT DISTINCT ID, Diameter_2
FROM tblDiameters;

Though it results in only 2 fields. How may the field: - DiameterMeasurement be brought in?

Many thanks:-)

Answer 1

You were on the right track to use a union. Here is one viable approach:

SELECT ID, 'Diameter_1' AS DiameterName, Diameter_1 AS DiameterMeasurement
FROM tblDiameters
UNION ALL
SELECT ID, 'Diameter_2', Diameter_2
FROM tblDiameters
ORDER BY ID, DiameterName;