Sql query to retrieve all rows with a unique column value

[skhanal]

You can use

SELECT <col1>, <col2>...
FROM table
GROUP BY rendering_provider_key

But you must use some grouping function like COUNT, MAX, MIN, SUM, AVG on all columns listed in SELECT list unless that column is part of GROUP BY list.

I am not exactly sure what your result set should look like, but even ORDER BY may work for you

SELECT *
FROM table
ORDER BY rendering_provider_key