Mysql check if column in a row is contained in another column?

I'm trying to make a mysql query that checks if a column in a row is contained within another column in the same row. Is there a way to do that kinda of query?

for example:

Key        Value         runHash  
2500       tacos         night.2500.293849284 
1775       windows       day.176555.43035842

I am trying to write a query that will return the second row and not the first because for the first row, Key is in runHash.

I tried to do:

select * from table where key not in runHash

However this doesn't appear to be valid for mysql.