SQLWorkBench/J starting a new instance…
As Thomas says below, you don’t have to start a new instance instead, do a File -> New Window
But if you did want a separate instance, here is what Thomas (Author of SQLWorkBench/J) says about that:
Thomas Kellerer
Otherwise it’s highly recommended to just open multiple Windows (File -> New Window)
If for some reason you really do need multiple instances instead of multiple windows, you can pass the command line parameter -singleinstance=true to skip the check for running instances. This applies to the new launcher that was introduced with build 127.
For previous builds (using the old launcher) you need to create a sqlworkbench64.ini that contains the line:
single.instance=none
The command line (console mode) never checks for an existing GUI instance.
Thomas