Can I get the position of a record in a SQL result table?

Question

If I do something like

SELECT * FROM mytable ORDER BY mycolumn ASC;

I get a result table in a specific order.

Is there a way in SQL

Answer 1

On databases that support it, you could use ROW_NUMBER() for this purpose:

SELECT RowNr
FROM (
    SELECT 
         ROW_NUMBER() OVER (ORDER BY mycolumn) AS RowNr,
         mycolumn
    FROM mytable
) sub
WHERE sub.mycolumn = 42

The example assumes you're looking for primary key 42 :)

The subquery is necessary because something like:

SELECT 
     ROW_NUMBER() OVER (ORDER BY mycolumn) AS RowNr
FROM mytable
WHERE sub.mycolumn = 42

Will always return 1; ROW_NUMBER() works after the WHERE, so to speak.