SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af19d385f9e82925a8f3cc69e00546cb96241d8afcc6beef8b25997a04e0b657' 
  AND token = 'Nf40YUgewPb4Dq4uNrlpNoXVoE2EFZ/5hERd7D0Lado=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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