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So don't worry so much about how to use  had had  as a unit of grammar, they will come together naturally when you want to express the verb ' to have ' in the past perfect. Let's consider a different verb for a moment like  to want .
As a side note (5+ years later), the HAVING clause is actually intended for use with grouped elements. However, it works with aggregate clauses (MIN, MAX, AVG) in most SQL engines even without a GROUP BY clause.