My first thought was that it is implausible for one to be performing a task just before they tell people about it in an interview. Having considered it twice, I realised it actually possible. Suppose a bloke wants to work for another company which happens to be situated beside his company. He can actually count the time and keep on working until the very last minute before rush out of his company and into the nrighbouring company. Then the bloke is able to use the OP's first sentence, just in time. Although I doubt anyone would practically want to do that.
And, this is probably not the sense of word
work the OP meant in his sentence. By
work, he probably wanted to mean
to have a job or to be employed. The more experiences one has, the more likely the interviewers will be in favour this person.
Then again, the interviewees is usually expected to have knowledge in a specific field, as they apply for a position related to the field. In this case, a interviewee's only having had a job before the interview is not sufficient for him to sucure his seeked position, regardless of whether they still have a job in another place or not, and even how many years of experiences they have.
To make the sentence clear, it can be rewritten as following:
In a job interview, it's always good to show that you've been working in the same field as the position you apply for.