跨數據庫查詢解決方案:
1:數據同步
2:dblink
DATABASE LINK:
創建DATABASE LINK的時候需要被訪問數據庫的IP地址,ssid以及用戶名、密碼。
1、創建
CREATE [PUBLIC] DATABASE LINK linkName
CONNECT TO userName IDENTIFIED BY password
USING 'connecting'
* connecting 爲在tnsnames.ora中定義的遠程數據庫的連接串。如果爲配置連接串,則直接將連接串寫在創建語句中
CREATE [PUBLIC] DATABASE LINK linkName
CONNECT TO userName IDENTIFIED BY password
USING '(DESCRIPTION =
(ADDRESS_LIST
=
(ADDRESS
= (PROTOCOL = TCP)(HOST = 192.168.0.123)(PORT = 1521))
)
(CONNECT_DATA
=
(SERVER
= DEDICATED)
(SERVICE_NAME
= mai)
)
)'
* 創建dblink必須有 創建連接的權限,登錄到遠程數據庫的賬號必須有 CREATE SESSION權限。
2、刪除
DROP [PUBLIC] DATABASE LINK linkName
3、查看已創建的
SELECT * FROM DBA_OBJECTS WHERE OBJECT_TYPE='DATABASE LINK'
SELECT * FROM ALL_DB_LINKS
select * from dba_db_links;
4、調用
[user.] table / view@linkName
5、同義詞
對於經常訪問的遠程數據庫連接,可以創建同義詞方便訪問。
CREATE SYNONYM synName FOR tableName@linkName