Variable column names using prepared statements

This indicates a bad DB design. The user shouldn't need to know about the column names. Create a real DB column which holds those "column names" and store the data along it instead.

And any way, no, you cannot set column names as PreparedStatement values. You can only set column values as PreparedStatement values

If you'd like to continue in this direction, you need to sanitize the column names (to avoid SQL Injection) and concatenate/build the SQL string yourself. Quote the separate column names and use String#replace() to escape the same quote inside the column name.

Prepare a whitelist of allowed column names. Use the 'query' to look up in the whitelist to see if the column name is there. If not, reject the query.

The accepted answer is not actually correct. While the OP approach indicated a bad DB design, it might be required by the business logic (for instance a MySQL IDE)

Anyway, for MySQL prepared statements, what you need to know is that ? is for values, but if you need to escape column names, table names etc, use ?? instead.

Something like this will work:

SELECT ??, ??, ?? FROM ?? WHERE ?? < ? 

Set values to ['id', 'name', 'address', 'user', 'id', 100]