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Gokul Ganesh
2,785 PointsSQL: Find all movies with any missing data
You need to find if any values in any of the columns are null. The columns are id, title, year released, genre;
SELECT * FROM movies WHERE id IS NULL OR title IS NULL OR year_released IS NULL or genre IS NULL;
This gave me the right answer.
Is there a simpler query ?
4 Answers
Alexandru Palita
14,261 PointsOr this...
SELECT * FROM movies WHERE id IN (title,year_released,genre) IS NULL ;
Eric Wilson
9,380 PointsIn the shortened query SELECT * FROM movies WHERE id IN (title, year_released, genre) IS NULL;, why do you use id between WHERE and IN?
Steven Parker
231,248 PointsI think you got it. 
SQL is known to get a bit wordy at times.
Aaren Isabel
6,842 PointsIS NULL is the way to indicate values that don't exist.
Here is my answer:
SELECT * FROM movies where year_released IS NULL;
Reed Benjamin
7,007 PointsReed Benjamin
7,007 Pointshelpful to remember, thanks!
Rachael Benedict
7,242 PointsRachael Benedict
7,242 PointsHi, thank you for this answer. Please could you explain how this works as I would like to understand it better. Thank you :)
Alexandru Palita
14,261 PointsAlexandru Palita
14,261 PointsThe SQL IN Operator The IN operator allows you to specify multiple values in a WHERE clause.
The IN operator is a shorthand for multiple OR conditions.
https://www.w3schools.com/sql/sql_in.asp
Keep learning ! You will figure it out... Succes!
Rachael Benedict
7,242 PointsRachael Benedict
7,242 PointsThank you for replying. I can understand all the IN examples in the link you posted below but I still don’t understand how the one in your own example is working :)
In the one below which is the last example from the link, it is saying select everything from customers table where the country column (from customer table) matches country column (from suppliers table) therefore displaying the rows where the countries match only
SELECT * FROM Customers WHERE Country IN (SELECT Country FROM Suppliers);
That makes sense to me but I can’t work out how your statement works and it looks like something I should know for the future. Thank you again and sorry for bothering!
Rachael
Alexandru Palita
14,261 PointsAlexandru Palita
14,261 PointsYou know what... You're right!
Now that i'm paying more attention , i understand that I read that so WRONG!
Sorry for any inconvenience.... my bad ... You've could just said: Hey dude ! Pay more attention :))... It's not what he's asking...
Thanks for noticing!
If you have like hundreds of columns not values... It's more advanced... Like you don't have to write hundreds of lines...
Check out this: https://stackoverflow.com/questions/63291/sql-select-columns-with-null-values-only https://stackoverflow.com/questions/12091272/find-all-those-columns-which-have-only-null-values-in-a-mysql-table