We use Custom properties heavily to control our alert behavior. Many of our alerts check to see if a certain custom property is empty. We have found when we perform a bulk update through the "Import Custom Properties" tool, there is no way to create an "empty" condition. According to SolarWinds, an "empty" field is a NULL in the database. When performing a bulk update, an empty field results in an empty string in the database. An empty string is not the same as a NULL and therefore the alert condition will not be met. If we edit a node, and save it without making any changes, the field then becomes a NULL.
I suggest the "Import Custom Properties" tool check to see if an imported value is blank, then assigns a NULL rather than an empty string. This would be more consistent with how the Edit Node functions.
