I am trying to do the following query with the alias in lowercase. Why if I put it in lowercase it gives me an error and in uppercase it works? Can aliases only be in uppercase?
Code:
SELECT nombre,poblacion AS "ciudad" FROM clientes ORDER BY ciudad;
Error:ORA-00904: "CIUDAD": identificador no válido 00904. 00000 - "%s: invalid identifier" *Cause: *Action: Error en la línea: 2, columna: 10