SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c0c1be314cc1f782fcf561064fa45b9dd2b47db00e6b77d5b9cbf0489debbd3' 
  AND token = 'YYVvR7FmAqNTHk7p7U+O1fbIg86BnUeld9IXGLuu0XI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00070

JSON explain

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