SQL Function that uses a time-stamp to output how old a question is
I have a calculated field whose value I want to modify depending on how old the entry is. Is there way in MySQL to take a time stamp and use it to determine how old a query is. 

Here is the calculated field

    ((ces.EXPERT_SCORE * cirm.CONSUMER_RATING) + (12.5 * scs.SIMILARITY)* (1 - EXP(-0.5 * (cal.TIPS_AMOUNT / ATV.AVG_TIPS)) + .15))AS ANSWER_SCORE

Basically, I want to multply this calculated field based on the age of a timestamp.
SQL Function that uses a time-stamp to output how old a question is
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I have a calculated field whose value I want to modify depending on how old the entry is. Is there way in MySQL to take a time stamp and use it to determine how old a query is. 

Here is the calculated field

    ((ces.EXPERT_SCORE * cirm.CONSUMER_RATING) + (12.5 * scs.SIMILARITY)* (1 - EXP(-0.5 * (cal.TIPS_AMOUNT / ATV.AVG_TIPS)) + .15))AS ANSWER_SCORE

Basically, I want to multply this calculated field based on the age of a timestamp.