SQL Null
NULL is a special value that matches missed data. It means there is no data inserted into the field.
There are operators to detect whether the value is NULL:
IS NULL: detects only values that equal to NULLIS NOT NULL: detects values that are not NULL.
12SELECT title FROM songs WHERE album IS NOT NULL
NULLdoes not match 0 or empty line, it only matches data that is missing and does not exist.
NULLvalues are ignored in theMIN,MAX,COUNT,AVG, andSUMaggregate functions.
Takk for tilbakemeldingene dine!
single
Spør AI
Spør AI
Spør om hva du vil, eller prøv ett av de foreslåtte spørsmålene for å starte chatten vår
Oppsummer dette kapittelet
Explain code
Explain why doesn't solve task
Awesome!
Completion rate improved to 4.17
SQL Null
Sveip for å vise menyen
NULL is a special value that matches missed data. It means there is no data inserted into the field.
There are operators to detect whether the value is NULL:
IS NULL: detects only values that equal to NULLIS NOT NULL: detects values that are not NULL.
12SELECT title FROM songs WHERE album IS NOT NULL
NULLdoes not match 0 or empty line, it only matches data that is missing and does not exist.
NULLvalues are ignored in theMIN,MAX,COUNT,AVG, andSUMaggregate functions.
Takk for tilbakemeldingene dine!
single