// Given an optional year, month, and day, we need to generate a timestamp
// to use as "WHERE rev_timestamp <= result"
// Examples: year = 2006 equals < 20070101 (+000000)
// Given an optional year, month, and day, we need to generate a timestamp
// to use as "WHERE rev_timestamp <= result"
// Examples: year = 2006 equals < 20070101 (+000000)