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A comment on The Next 50 Years of Databases (2015). Parent comment

Re:The Next 50 Years of Databases (2015) by paulddraper on Monday November 11, 2019 @10:51PM (#21511364)
You virtually always want this.

   SELECT count(*), favorite_color, favorite_song
   FROM person
   GROUP BY ...
The "..." is of course favorite_color, favorite_song.

Whether you want this or not, ANSI SQL requires that you group by at least these.

You could group by more more fields, such as favorite_pet, though that would be somewhat odd since you are did not include it in the result set.

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Re:The Next 50 Years of Databases (2015) by jimktrains2 on Monday November 11, 2019 @11:15PM (#21511465)
Ah, you meant in the select, not the table. I guess I'm just much more in favour of being explicit, but I can understand the usefulness of what you said now that I fully understand it.
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