SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae1055ced985c74a4b9b716d09487cfa0f779f41dabaea2ee0a2efd89e980fa8' 
  AND token = 'cS1Gezvi9mucLaUn+Llo36Yo6F5oqERM0nUOYtVPGjo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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