How To Propagate User Identity Form Application Server To Database

Hi All,

I am new to MS SQL SERVER 2005.
My web application using SQL Server 2005 as back end database to store all the information.
I am using connection pooling to get connection form db.
But my fron end user( user who logged in into webapplication) lost his identity b'coz for database user is application server.
Now I wanna to track front end user in db.

In oracle I can do it by using CLIENT_IDENTIFIER. But in sql server I don't know how to do it.

in oracle i can do it as below
public void setIdentity(Connection conn, String identity) {
PreparedStatement ps;
try {
ps =
conn.prepareCall("begin dbms_session.set_identifier(?); end;");
ps.setString(1, identity);
ps.execute();
ps.close();
} catch (SQLException e) {
// Handle the exception
}
}
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once the transaction is complete, the application should reset the identity as follows:

public void clearIdentity(Connection conn) {
PreparedStatement ps;
try {
ps = conn.prepareCall("begin dbms_session.clear_identifier(); end;");
ps.execute();
ps.close();
} catch (SQLException e) {
// Handle the exception
}
}
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Please guide me for same.

Thanx in advance.

Bhadu<!--[endif]-->