
Im trying to copy the above data from SQL Server to Amazon Redshift. Unfortunately I found that the characters in catdesc column are replaced by '?'(i.e., question mark).

Can any one suggest on this?
Redshift should be able to load in UTF8 characters, you need to use the VARCHAR data type with enough space to handle the multibyte characters.
There's some more information here: Loading Multibyte Data from Amazon S3 and here: Handling UTF-8 Characters in Redshift