SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a79987092befe4ac9acebb5be14abce63ef1eefc0f71d19c89dae37a916f39c' 
  AND token = 'saMoLjwpSGYYnIvekv8UuwExIWnN95LfzyJNZUgJI0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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