Your hash keys are always a singles strings. You can of course chose something like time and conference, separated by a special character, as a combined key - but what would you gain?

In general a Hash is a String-to-Thing mapping, not a relational database.

(oh, and please use <code>...</code> tags around example code that you post here, that'll make it easier to read).

In reply to Re: question about multi value hash key by moritz
in thread question about multi value hash key by joybee

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