SQL Select unique value in a column

Question

I have a table like this:

ID  CatID  Filename
 1    1      abc
 2    2      abc
 3    3      cat
 4    2      dog
 5    1      dog

What I want to do is get just 1 ID per filename. I dont mind what ID i get i.e. the first or the last. How would I go about doing this?

Answer 1

SELECT MIN(ID), FileName
FROM YourTable
GROUP BY FileName

Will get you the first ID for each filename

Answer 2

-- Will get you the min
SELECT MIN(ID), FileName
FROM table
GROUP BY FileName

-- Will get you the max
SELECT MAX(ID), FileName
FROM table
GROUP BY FileName