delete from dspam_token_data 
  where (innocent_hits*2) + spam_hits < 5
  and julianday('now')-julianday(last_hit) > 30;
delete from dspam_token_data
  where innocent_hits + spam_hits = 1
  and julianday('now')-julianday(last_hit) > 15;
delete from dspam_token_data
  where julianday('now')-julianday(last_hit) > 90;
delete from dspam_signature_data
  where julianday('now')-julianday(created_on) > 15;


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