SELECT TOP 1 in wp_query for each groupby meta value
Is there any way using wp_query class to execute SELECT TOP 1 sql command while using groupby for each meta_value results. I need the wp_query to select only the first one of each groupby meta_value results. Cant find on google any example with wp_query! I can only find sql queries using get_posts wordpress function but i dont want to use get_posts. Any help appreciated.