Probably for a small table, where the machinery of reading the index,
followed by checking the table for non-visible tuples is more costly
than just scanning the table!
regards
Mark
John Hansen wrote:
>Why not just change the function all together to 'select $1 from $2
>order by $1 desc limit 1;'
>
>Is there ANY situation where max(col) as it is, would be faster?
>
>... John
>
>
