SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f48acd9f5e74c9e74033203aabd12b674321b2b82029f5cfaa48a520a758c52e' 
  AND token = '6fX/h5yvM8ByfTTGpO/KQdgOkZZhZXiiieLr+tYqwm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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