Do you have the sqlparam plugin turned on in 3.8.0 and/or 3.7.1? I believe I have found why SQuirreL hangs when you have comments embedded inside your SQL. Using jvisualvm, I have traced the problem to the mentioned plugin. Specifically, SQLParamExecutionListener.java, line 99: // Removes /* */ comments sql = sql.replaceAll("/\\*(.|\\s)*\\*/", ""); Not only is this code flawed (if you have multiple multiline comments in your SQL, it's possible that it will strip everything from the first to the last...