The one difference between a technical job interview and other interviews is that the interviewer has an assortment of questions with tangible answers. These black and white answers leave little room for the job seeker to use their creative abilities. Therefore the best way to handle the technical question you don’t know is with the following simple reply – “I DON’T KNOW.”
The reason for such a blatant admission of “not knowing” is to build a feeling of trust between you and the interviewer. If you bluff, guess at the answer, or make false claims that become more evident as the interview progresses, you will lose credibility and all additional or previous non-technical questions will become suspect. And who will make a job offer to a person they don’t trust?
However, if the opportunity exists, one technique that can be used to build trust, confidence and give the potential job seeker an opportunity to capitalize on his/her knowledge, is to ask the interviewer for an EXPLANATION AND EXAMPLE OF HOW AN UNKNOWN TOOL IS USED. During the reply, listen very carefully, absorbing as much information as possible. After you have questioned the interviewer thoroughly and are confident – and I stress confident – that you understand the answer, relate the use of this tool to an aspect of technology you have worked with. For example, suppose you are being questioned on a function of Sybase – you might respond with similar concepts you’ve used with Informix.
The point to make to the interviewer is that you understand the unknown technology and can adjust to it with little difficulty. the interviewer will know that you are bright, a quick learner, and will not bluff when the heat is on.