Oracle AUDSID equivalent in SQL Server 2012

Question

What is the equivalent SQL Server 2012 code for this please ?

 IF INSERTING THEN
            :NEW.audsid:=SYS_CONTEXT('USERENV', 'SESSIONID');

Answer 1

Oracle and SQL Server handle triggers very differently. Oracle has the concept that a trigger affects only one row at a time. SQL Server doesn't. Instead, it uses a "table" inserted with the new rows.

So, your question has three parts:

1. What is the equivalent of INSERTED ?
2. What is the equivalent of SYS_CONTEXT('USERENV', 'SESSIONID') ?
3. What is the best way to do this in SQL Server?

Here is the answer to the first two questions:

if (exists (select 1 from inserted) and (not exists (select 1 from deleted))
    update inserted
        set audsid = @@SPID;

However, in most cases, you would just use the default keyword in the column definition:

audsid int default @@SPID

Much easier and a trigger isn't needed.