For extension version 2.1.0 or newer

  1. Select menu Tools -> Features.
  2. Choose Installed Updates.
  3. Select Schema Visualizer and click Uninstall button.

For extension version 2.0.1 or older

  1. Exit Oracle SQL Developer.
  2. Delete file sqldev_path/sqldeveloper/extensions/com.sumsoftsolutions.erd4oracle.sqldev.jar
  3. Delete directory sqldev_path/sqldeveloper/extensions/com.sumsoftsolutions.erd4oracle.sqldev

  4. Where sqldev_path is your SQL Developer installation directory.
    On Mac OS/X the sqldev_path is usualy /Applications/SQLDeveloper.app/Contents/Resources/sqldeveloper/