Yesterday I faced a situation in one of SSAS cubes, which dimension processing was failed because it found two different members with different attribute values, like Auckland and auckland !
I found out that reason of this problem is SSAS dimension will inherits its collation from underlying database and if you don’t change the setting it might use case sensitive collation. and if this find two different member with different case sensitivity in attribute key columns it will fail processing.
There are two ways for solving this issue:
1- use functions like UPPER , LOWER to change case sensitivity in queries used in DSV.
you might also like to capitalize your words or sentences, I’ve wrote another post and a SQL Server function for Capitalizing words and sentenses here, you can use it simply.
2- change collation of dimension to a case insensitive.