How do I select just any one row of multiple instances?-CodePudding

I have a table that looks something like this

and I want something like this where we just pick one row of all the distinct nums but only one.

city	num	something
LA	1233	av
SF	426	ah

What query method would be most effective at getting the second table?

I chose LA 1233 av at random. I do not care what specific instance of 1233 that I get, just that I only get.

CodePudding user response：

here is one way :

select * from ( 
   select * , row_number() over (partition by num order by random()) as rn
   from tablename
) t where rn = 1

which return random select each time , but if you don't care use a column like city in your order by clause.