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Difference between @@Identity, Scope_Identity (), IDENT_Current(‘tablename’)

Problem: Which one of the following should be use to get the last Identity of the recently added row in T-SQL or Stored Procedure: @@Identity, Scope_Identity (), IDENT_Current(‘tablename’)
Solution: So many times we required to get the last inserted rows identity to be insert them in child table for reference in stored procedure. All the above statements gives us the last identity inserted but in different perspective.
So if you want to get the last identity in T-SQL or Stored Procedure always use Scope_Identity () to avoid problems in Multiuser (concurrent) scenarios. Let me explain why?
Lets see what does each means?
@@Identity :
It returns the last IDENTITY value produced on a connection, regardless of the table that produced the value, and regardless of the scope of the statement that produced the value.@@IDENTITY will return the last identity value entered into a table in your current session. While @@IDENTITY is limited to the current session, it is not limited to the current scope. If you have a trigger on a table that causes an identity to be created in another table, you will get the identity that was created last, even if it was the trigger that created it.
Scope_Identity () :
It returns the last IDENTITY value produced on a connection and by a statement in the same scope, regardless of the table that produced the value.SCOPE_IDENTITY(), like @@IDENTITY, will return the last identity value created in the current session, but it will also limit it to your current scope as well. In other words, it will return the last identity value that you explicitly created, rather than any identity that was created by a trigger or a user defined function.
IDENT_Current(‘tablename’):

It returns the last IDENTITY value produced in a table, regardless of the connection that created the value, and regardless of the scope of the statement that produced the value.IDENT_CURRENT is not limited by scope and session; it is limited to a specified table. IDENT_CURRENT returns the identity value generated for a specific table in any session and any scope.

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