text: ALTER TABLE shares
  ADD COLUMN accepted TIMESTAMP NOT NULL;
  
  CREATE INDEX IDX_SHARES_POOL_ACCEPTED ON shares(poolid, accepted); 
  CREATE INDEX IDX_SHARES_POOL_MINER_ACCEPTED ON shares(poolid, miner, accepted);
  
  ALTER TABLE shares
  ADD COLUMN processed TIMESTAMP NULL;
  
  CREATE INDEX IDX_SHARES_POOL_PROCESSED_ACCEPTED ON shares(poolid, processed, accepted);
  