SQL Distinct
Distinct is a keyword used with SELECT to return only unique values. Usually, you want to get all unique values, but there are duplicate values stored in the tables.
Check the difference: in our table, there are 18 records at all, and each record has a singer. You'll retrieve the 18 singers with the next query:
12SELECT singer FROM songs
But some singers, for example, AC/DC, occur multiple times. To retrieve the unique singers, use the DISTINCT keyword before the singer column:
12SELECT DISTINCT singer FROM songs
Now there are no repeated values, so you can see that the total number of unique singers is 10.
Swipe to start coding
Find all unique title values in songs.
Løsning
Tak for dine kommentarer!
single
Spørg AI
Spørg AI
Spørg om hvad som helst eller prøv et af de foreslåede spørgsmål for at starte vores chat
Opsummér dette kapitel
Explain code
Explain why doesn't solve task
Awesome!
Completion rate improved to 4.17SQL Distinct
Stryg for at vise menuen
Distinct is a keyword used with SELECT to return only unique values. Usually, you want to get all unique values, but there are duplicate values stored in the tables.
Check the difference: in our table, there are 18 records at all, and each record has a singer. You'll retrieve the 18 singers with the next query:
12SELECT singer FROM songs
But some singers, for example, AC/DC, occur multiple times. To retrieve the unique singers, use the DISTINCT keyword before the singer column:
12SELECT DISTINCT singer FROM songs
Now there are no repeated values, so you can see that the total number of unique singers is 10.
Swipe to start coding
Find all unique title values in songs.
Løsning
Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående mulighederTak for dine kommentarer!
Awesome!
Completion rate improved to 4.17single
