I am getting the following exception:
Caused by: org.postgresql.util.PSQLException: ERROR: character 0xefbfbd of encoding \"UTF8\" has no equivalent in \"WIN
Don't eridicate the characters, they're real and used for good reasons. Instead, eridicate Win1252.
What do you do when you get this message? Do you import a file to Postgres? As devstuff said it is a BOM character. This is a character Windows writes as first to a text file, when it is saved in UTF8 encoding - it is invisible, 0-width character, so you'll not see it when opening it in a text editor.
Try to open this file in for example Notepad, save-as it in ANSI encoding and add (or replace similar) set client_encoding to 'WIN1252'
line in your file.
I was able to get around it by using Postgres' substring function and selecting that instead:
select substring(comments from 1 for 200) from billing
The comment that the special character started each field was a great help in finally resolving it.
I had a very similar issue. I had a linked server from SQL Server to a PostgreSQL database. Some data I had in the table I was selecting from using an openquery statement had some character that didn't have an equivalent in Win1252. The problem was that the System DSN entry (to be found under the ODBC Data Source Administrator) I had used for the connection was configured to use PostgreSQL ANSI(x64) rather than PostgreSQL Unicode(x64). Creating a new data source with the Unicode support and creating a new modified linked server and refernecing the new linked server in your openquery resolved the issue for me. Happy days.