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

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

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.

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.