php - 如何选择具有 UNION 结果的表名？

Question

这是 UNION 的结果，但我还想知道与每一行关联的源表:

SELECT City FROM Customers
UNION
SELECT City FROM Suppliers
ORDER BY City;

查询的实际结果是这样的:

city
572
123

但我想要这样的结果:

city tablet_result
572 Customers
123 Suppliers

Answer 1

SELECT City, 'Customers' as tablet_result FROM Customers
UNION
SELECT City, 'Suppliers' as tablet_result FROM Suppliers