Update: This issue is now fixed in MySQL Workbench 6.3.9

After upgrading MySQL Workbench 6.2 to 6.3, my Workbench displayed Mac’s spinning wheel of death almost all the time, even with the most simple query:

SELECT * FROM ecruite.MenuItem;

The queried table consists of 4 rows with 10 columns each and approx. 10 characters each. So it should be done in no time. Except if you’re using macOS Sierra and MySQL Workbench 6.3 you get the spinning wheel.

According to a user on SO, it’s a known bug and popped up with the introduction of a new security feature in Sierra: “Gatekeeper Path Randomization“.

As long as there is no bug-fixed version of MySQL Workbench, here is a workaround until MySQL releases a new version:

1. Open MySQL Workbench :)
2. Right click on your connection (most likely “localhost” or “127.0.0.1”)
3. Choose “Edit connection”
4. On the right hand window select “Connection > SSL”
5. Change “Use SSL” from “If available” to “No”
6. Now click on the tab “System Profile”
7. Choose “MacOS X” as System Type
8. Click “Test connection”

Now open the edited connection in a new tab and open the same connection again in a second tab. For whatever reason, the ever-loading queries were gone and I got my results within no time – 0.00051s for the before-mentioned query.

Sources:
Bug #83658
SO Thread: MySQL Workbench hangs on simple queries
Sierra and Gatekeeper Path Randomization