1set cte_max_recursion_depth=5000; 2 3flush status; 4with recursive q (b) as 5(select 1 union all select 1+b from q where b<2000) 6select min(b),max(b),avg(b) from q; 7show status like 'Created_tmp_disk_tables'; 8 9--echo # Test when conversion to InnoDB affects recursive references which 10--echo # are not open yet (those of q1): 11flush status; 12with recursive q (b) as 13(select 1 union all select 1+b from q where b<2000) 14select min(q.b),max(q.b),avg(q.b) from q, q as q1; 15show status like 'Created_tmp_disk_tables'; 16 17--echo # Same, but make q1 the writer; this is to test overflow when 18--echo # the writer isn't first in the 'tmp_tables' list 19 20flush status; 21with recursive q (b) as 22(select 1 union all select 1+b from q where b<2000) 23select min(q.b),max(q.b),avg(q.b) from q right join q as q1 on 1; 24show status like 'Created_tmp_disk_tables'; 25 26--echo # Test when outer query reads CTE with an index. 27--echo # Overflow doesn't happen at same row as queries above, as this 28--echo # table has an index which makes it grow faster. 29 30let $query= 31with recursive q (b) as 32(select 1 union all select 1+b from q where b<2000) 33select min(b),max(b),avg(b) from q where b=300; 34 35eval explain $query; 36show status like 'Created_tmp_disk_tables'; 37eval $query; 38show status like 'Created_tmp_disk_tables'; 39 40--echo # Verify that rows come out in insertion order. 41--echo # If they didn't, the sequences of @c and of 'b' 42--echo # would not be identical and the sum wouldn't be 43--echo # 1^2 + ... + 2000^2 = n(n+1)(2n+1)/6 = 2668667000 44 45set @c:=1; 46flush status; 47with recursive q (b, c) as 48(select 1, 1 union all select (1+b), (@c:=(@c+1)) from q where b<2000) 49select sum(b*c) from q; 50show status like 'Created_tmp_disk_tables'; 51