selectlist field that editors can add options to

I am not sure about this

I am trying to understand this 2.

I notice this field only this week. And a tutorial or doc would be nice so see what it does.

Does anyone have this working? Can I see it in action?

This field was added by enjoyman at first, i tried to make sense out if.

It seems that enjoyman originally add it , to be able to use a SQL query when creating the filter, thus via the query you can select which field values to show in the filter (see parameters)

1. I have cleaned up the filter and added better descriptions and more parameters.

2. After our discussion here i see that this field makes sense to make this field display not only text field but also drop-down select of existing values, thus it will be more useful and its name will make complete sense

Great I will try to make something of it. I will ask for help if needed. Thanks.