added body for search query

Nothing to search for atm, so only the fail test works.
added condition for null saved value in search

Distinct from a failed search null is the MySql null value saved at the
query location, where we will return an empty string in that case.
added TODO note
result defaults to null in search
allowed for returning other invalid data types

If the result cannot be cast to string, and it is not an Sql Null value,,
the search function returns null, indicating an error.