В разборе задачи №5 я писал, что COUNT(DISTINCT id) лучше, чем COUNT(*), т.к. помогает в том числе избежать дублей при джоинах. В текущей задаче дублей при джойнах не наблюдается, но все равно пример показательный. Видим, что для пассажира 'Michael Caine' COUNT(DISTINCT trip) дал результат 3, а COUNT(*) = 4.
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With the help of the Search Filters option, users can now filter search results by type. They can do that by using the new tabs: Media, Links, Files and others. Searches can be done based on the particular time period like by typing in the date or even “Yesterday”. If users type in the name of a person, group, channel or bot, an extra filter will be applied to the searches.
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