SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a72996023bf3123e5a1b3f8c7edba4fc534485bf631a07f710ebacc3816835e' 
  AND token = '3S5dkwJvsyRpO7ym0QvophfeA1JTMmSJVbkuzhsMsWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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