Browsed (googled) around with this question but could not find a definitive answer...

I have 20 columns containing numbers. All numbers are unique in row.
How can I find all the rows containing single value, that can be in any of the 20 columns?

This far I have only seen solutions like
WHERE col1=1 OR col2=1 OR col3...

While I can produce these queries without breaking a sweat with code, in my eternal quest for knowledge and more elaborate (efficient) solutions I present my question to you: Really, no other way than the one mentioned above?

Thanks for any input!