data in sqlserver is not case sensitive

I am facing problems as the data in sqlserver is not case sensitive. The data in parent key may be capital/lower case and the same data in the child table may be lower/capital case. While migrating the data from sqlserver database to other databases(like oracle) its giving error as the data not found in parent key, though the data found in parent table . This is just because the case sensitive in oracle. But according to my knowledge its better if the sqlserver also supports data case sensitive.

Take a small example
Need a table to store all the alphabets in a table
the table structure is

CREATE TABLE [dbo].[ALPHABET] (
[Alphabet] [varchar] (1) NOT NULL ,
[Description] [varchar] (50) NOT NULL
)
GO

The data is

Alphabet

Description

a

Small a

b

Small b

C

Capital C

A

Capital A

sqlserver wont allow to insert data 'A' and gives error "voilation of primary key", though a & A are different according to this table.

I tried with NVARCHAR datatype also. The same problem here also. Sqlserver atleast should support data case sensitivity for NVARCHAR datatype as this can store different languages. May be in other languages the entire meaning may be differ with case differences. Even in english language some words meaning will differ with case differences. For reference can refer english dictionary

change the collation if the field you want to be case-sencetive into SQL_Latin1_General_CP1_CS_AS