SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dbc7472184fe387b5be4bb6785ce7467e5b5cba24b0624bebdb22d1226601ee' 
  AND token = 'XNAU6Qtt/GO2HmlNmiI2Nivl1WflXTjSzrQ3ArqHUGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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