SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1392b0fbc5a52135224d69fdc1a37948ae89a770c3f5a1e44e4355719df7b5b' 
  AND token = 'tBNWPWHh18fXLkBKF1qBDMux/LIbBVqZ66PcpHssSaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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