for each row rp in table p 
  for each row rq in table q
    if rp and rq satisfy the join condition
      output the comjoined rows  

- needs rowcount_p * blockcount_q + blockcount_p block transfers, and

- needs rowcount_p + blockcount_p seeks. - runs in O(|rowcount_p||rowcount_q|) I/Os.

It can be improved to a block nested loop by using read blocks:

for each blockp in p
  for each row in q
    for each row in blockq 
      if the rows the join condition
        output the conjoined rows

Last updated 16 Aug 2024