如何能形成一种“Oracle”观点,在两种不同情况下使用两种图象的数据?
我们知道,在同样情况下,如何用两个图表来做到这一点:
CREATE VIEW MYVIEW AS
SELECT X,Y,Z FROM A.MYTABLE
UNION
SELECT X,Y,Z FROM B.MYTABLE
但是,如果图象<代码>A和B
不同,那么甲骨质如何?
如何能形成一种“Oracle”观点,在两种不同情况下使用两种图象的数据?
我们知道,在同样情况下,如何用两个图表来做到这一点:
CREATE VIEW MYVIEW AS
SELECT X,Y,Z FROM A.MYTABLE
UNION
SELECT X,Y,Z FROM B.MYTABLE
但是,如果图象<代码>A和B
不同,那么甲骨质如何?
You could create a database link: http://download.oracle.com/docs/cd/B28359_01/server.111/b28310/ds_concepts002.htm#ADMIN12092 and then do
CREATE VIEW MYVIEW AS
SELECT X,Y,Z FROM A.MYTABLE
UNION
SELECT X,Y,Z FROM B.MYTABLE@<LinkName>
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