How to change a product dropdown attribute to a multiselect in Magento ?

February 20, 2015 Iyngaran Iyathurai 0

First, update the attribute input type to multiselect:

  Next, copy the attribute values from the old table to the new:  

  Finally,  remove the old values or they will conflict with the new setup (the old values will load, but Magento will save new values to the varchar table):