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Development Tools Database Foundations Reading Data from Databases with SQL Dealing with NULL

Posted by Becca Ades
Becca Ades
4,205 Points

I don't understand what this question is asking me to do: Select all movies with the "year" column that hasn't been popu

What does it mean that a column hasn't been populated?

2 Answers

Brian Flood
Brian Flood
20,037 Points
Brian Flood
Brian Flood
20,037 Points

They are asking you to select movies where there is no value in the "year" column. In SQL the absence of a value (aka not being populated) is known as NULL.

Jeshua Dunham
PLUS
Jeshua Dunham
Courses Plus Student 8,499 Points
Jeshua Dunham
Jeshua Dunham
Courses Plus Student 8,499 Points

When a column isn't assigned a value in a row it will have a 'NULL' value in the database. The question is asking you to search for only the results whose year column was never assigned -- or IS NULL.