usare union in una view

[Fumocamel]

c'è qualche restrizione nell'usare una union in una view??

tipo:

DROP VIEW IF EXISTS `meseview`; 
 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`%` 
SQL SECURITY DEFINER      VIEW 'meseview`  	AS  		
( (select datapartenza as datadainserire, concat(glmese(month(datapartenza)),' ', year(datapartenza)) as chedata 
from contratti group by month(datapartenza)) 
union  
(select datapartenza as datadainserire, concat(glmese(month(datacontratto)),' ', year(datacontratto)) as chedata 
from contratti group by month(datacontratto)) )

[Fumocamel]

azz ho risolto togliendo le parentesi...

DROP VIEW IF EXISTS `meseview`; 
 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`%` 
SQL SECURITY DEFINER      VIEW 'meseview`  	AS  		
(select datapartenza as datadainserire, concat(glmese(month(datapartenza)),' ', year(datapartenza)) as chedata 
from contratti group by month(datapartenza)) 
union  
(select datapartenza as datadainserire, concat(glmese(month(datacontratto)),' ', year(datacontratto)) as chedata 
from contratti group by month(datacontratto))