As you know in Oracle 11g passwords are case sensitive by default. This applies to connecting via SQL*Plus or other client tools. And it also applies to database links between databases. So when you link from Oracle 10g to Oracle 11g create database link like this:
CREATE DATABASE LINK my_linkDo not forget to enclose password by double-quote marks!
CONNECT TO remote_user IDENTIFIED BY "CaSe_SeNsItIvE_PaSsWoRd"
When you do not set password this way, you will be getting:
ORA-01017: invalid username/password; logon denied.Hope this small tip will be useful for someone.
More on Creating Database Links.
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