select store_name from store_information where country is null union select store_name frOm store_information where country='USA';
执行正常
select store_name from store_information where country is null minus select store_name frOm store_information where country='USA';
显示Incorrect syntax near 'minus'.
求原因
执行正常
select store_name from store_information where country is null minus select store_name frOm store_information where country='USA';
显示Incorrect syntax near 'minus'.
求原因
(select store_name from store_information where country is null )
minus
(select store_name frOm store_information where country='USA')
*问题原因可能是表结构不同或者数据库不支持这个指令!
*/
minus
select store_name from store_information where country is null
执行时候将两个select分别执行出两个结果。。