I think you are better of using Action Grid for this. You can create a list or grid, based on your SQL statement.

The Bind expression is indeed a rule that defines whether a field is shown or not. 

If you don't have action grid, you can use 2SXC (free) or Live visualizer (commercial)

thanks, we don't have Action Grid, at least not at the moment. 
Last time I looked at 2SXC I found it confusing and would rather steer clear of that at the moment if possible.

It was suggested that extracting columns might work (under Events >> On Page Load >> Extract Column, and using that as a token but that's not working at the moment either.

think I'm getting closer to a solution using "Create List from SQL" action and "For Each List Entry" , although I still cannot get it working.

Here's what I've got so far, 

1. Created an action form with a user text box to retrieve their input > Called "UserTxt"
2. On the submit btn of the form, I've used: "Create List from SQL" 
3. on the above SQL Query used - "SELECT MyField FROM dbo.MyDummyTable"
4. Given the list the name 'MyList', 
5. ADD >> Execute Actions For Each List Entry, 
6. ?  some conditions ?
7. Action List >> Display Message >> e.g. 'success message, match found'

I think the issue is around step 6?, perhaps its just a case of formatting the condition under Execute Actions? such as :

[ < MyList> == < UserTxt > ]
or
[ < MyList > : < MyField > ] == < UserTxt > ]

I have tried formatting the conditions in a variety of ways and even without any conditions but nothing happens either way - the display message is never shown. Am I missing something? or does it look OK, and in which case it might be just a formatting/typo issue?