SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3aa22545603b293ac9e58867f167b0a872d5c78d1808809fc17308ac75d0825b' 
  AND token = 'AsqyYnBfumWbJ8pyiMt9cRoqim1dbqgNwBxWO3X5zEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}