The records below are definitely not sorted by r...
select id, name, rand() r from countries order by r limit 10;
Query: select id, name, rand() r from countries order by r limit 10
Query finished, fetching results ...
+----+----------------+-----------------------+
id | name | r |
+----+----------------+-----------------------+
3 | Canada | 0.0004714746030380365 |
5 | Australia | 0.5895895192351144 |
1 | United States | 0.4431900859080209 |
4 | Ireland | 0.0739258840093044 |
6 | Netherlands | 0.4621509646354946 |
2 | United Kingdom | 0.6679162032287178 |
9 | France | 0.8352529978543767 |
8 | Germany | 0.1610932858479644 |
7 | New Zealand | 0.4815021690360746 |
91 | Antigua | 0.5511845208477156 |
+----+----------------+-----------------------++----+----------------+-----------------------+
3 | Canada | 0.0004714746030380365 |
5 | Australia | 0.5895895192351144 |
1 | United States | 0.4431900859080209 |
4 | Ireland | 0.0739258840093044 |
6 | Netherlands | 0.4621509646354946 |
2 | United Kingdom | 0.6679162032287178 |
9 | France | 0.8352529978543767 |
8 | Germany | 0.1610932858479644 |
7 | New Zealand | 0.4815021690360746 |
91 | Antigua | 0.5511845208477156 |
Returned 10 row(s) in 0.48s