Hello @89sankar,
it is completely as @LinusH said.
My addition here is an explanation on how SAS handles Excel and Access "files" and why, and why you find those differences.
The reason is that Excel is not much more different than a csv file. It is a "kind-of-text file". But Access is a perfectly binary file.
Also, Excel I would not consider it as a database, while Access it is a database. A small and simple one but, still, a relational database with full specifications. Hence, Access will be handled as a normal database within SAS, Excel, as a "comma-separated" file.