Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '657866fb051e47f6bb3d029e718ce3afcfe1ce81720027dbe7f8659991f2fb8a' 
  AND token = 'b9bIJ+nS3NLIhSCtt7JFOwUay+xogJJSPHBRdYedT9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}