Can build the regexp out here. Be sure to use /i modifier for case insensitivity:
```ruby
UNSCOPING_OPERATORS = ['IS', '=', '!=', 'IS NOT', '<', '>', '<=', '>=']
MATCH_UNSCOPING_OPERATOR = /(#{Regexp.union(UNSCOPING_OPERATORS.map { |op| Regexp.escape op })})/i
```