Aggregates with DISTINCT

Language:Project:Language policy	English  • 日本語

COUNT DISTINCT

You can find the number of different values using COUNT with DISTINCT

In 1915 four prizes were awarded in three different subjects:

SELECT yr, subject, winner FROM nobel WHERE yr=1915

yr subject winner 1915 Chemistry Richard Willstätter 1915 Literature Romain Rolland 1915 Physics Lawrence Bragg 1915 Physics William Bragg

COUNT(subject) gives 4; COUNT(DISTINCT subject) gives 3.

SELECT COUNT(subject), COUNT(DISTINCT subject)
  FROM nobel
 WHERE yr = 1915

SELECT COUNT(subject), COUNT(DISTINCT subject)
  FROM nobel
 WHERE yr = 1915