How to store dataset in session variable

To use session brings a few problems:
1. Data stored on session gone when session is out (user went to drink a coffee)
2. Session data uses the memory of the host computer, so big/numerous sessions can cause performance problems if hardware is not scaling with...

It is absolutely unclear from where those 15 records came, but it was better to pass only single parameters between pages and not junk of data...
For instance when you open a list of books of an author, where the author picked from a list, you only pass the author id to the next page and it is the responsibility of that page to load the list of relevant books...

It is not the good practice to store a list of records in session.

In the first page from where you get the data?
Same way you can retrieve the list of records in 2nd page by passing the single parameter in 2nd page by the help of session.

let say:
You have a list of records of one ID in first page. You can pass that ID as parameter in 2nd page by the help of session.

Ex:

Firstpage:

Session["Keyname"]="YourValue";


2nd Page:

You can retrieve the list of records in of that session key.

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As per the question if you want to set the ds to session then here is the code.

Set: In first page
DataSet ds=new DataSet();

Session["KeyName"]= ds;

Get in 2nd page:

DataSet ds= (DataSet) Session["KeyName"];

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