Do I need my databases' client software to be installed to connect r9.x CA ERwin DM to the r9.x Mart? Matt Russo Updated November 05, 2019 14:25 Follow Solution: no database client software is needed for r9 CA ERwin DM to connect to the r9 mart. r9 ERwin establishes the connection to the mart using JDBC (Java Database Connectivity). Related articles Using r9 erwin DM, I am attempting to login to my mart using my database user, however, that is not working. I get the error ' Cannot pass null or empty values to constructor ' Comments 0 comments Please sign in to leave a comment.