SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd84e4d21aa8792ecfaf9e336dedcd62616f05f01218680e4b946ca99dcb71299' 
  AND token = 'yhl7hI4Y6JtblvaZO5zRfW4aagxTP73HSXH9HmHxzlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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