sphinx9999 Posted February 14, 2008 Share Posted February 14, 2008 Which do you think is better, DISTINCT or GROUP BY? SELECT DISTINCT id FROM phrase WHERE campaign LIKE 'proper%' or SELECT id FROM phrase WHERE campaign LIKE 'proper%' GROUP BY advert_id I've asked this question before and received the following answer from a reliable source: "When there's just one column it doesn't matter". Do you agree? Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/ Share on other sites More sharing options...
Daniel0 Posted February 14, 2008 Share Posted February 14, 2008 It depends on what you're trying to do. Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-466826 Share on other sites More sharing options...
aschk Posted February 14, 2008 Share Posted February 14, 2008 GROUP BY Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-466833 Share on other sites More sharing options...
jaymc Posted February 15, 2008 Share Posted February 15, 2008 Benchmark it ;-) phpmyadmin is good, it tells you time taken to execute a query Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-467726 Share on other sites More sharing options...
freenity Posted February 26, 2008 Share Posted February 26, 2008 I know old topic, but have a look at this: http://gwphp.feudal-times.net/?p=5 benchmarked and everything Guess who wins Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-477195 Share on other sites More sharing options...
fenway Posted February 27, 2008 Share Posted February 27, 2008 This is mainly because distinct is a filesort operation which group by has the chance to use an index or some temporary filesorting on smaller sets along the way. Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-478286 Share on other sites More sharing options...
goldfiles Posted April 16, 2008 Share Posted April 16, 2008 Group By usually Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-518202 Share on other sites More sharing options...
abs0lut Posted August 24, 2008 Share Posted August 24, 2008 i will not use distinct anymore Link to comment https://forums.phpfreaks.com/topic/91044-distinct-or-group-by/#findComment-624209 Share on other sites More sharing options...
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