SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ff8bc7073d3c7e8e4e13a3434c8dc32f31ba84c066a81c841491505ad8fd820' 
  AND token = 'i9wHgY55hRndIfUr0GtfmuSSufyzoF5jPtrjO3N7LPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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