Yeah, I did actually mean that he can rewrite his DB code so it would look like: 

for (1..5) {
  # select content of table $_ into temp table
}
for (1..10000) {
  # crosscheck with temp table
}

[download]
and it's possible (it depends on exact requirements) that the later loop may be replaced with a single DB query.

In reply to Re^3: how do hashes work - complexity question by zwon
in thread how do hashes work - complexity question by baxy77bax

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