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Get Identity value of the recently added record

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The below three built-in functions can be used to get the identity of the mostly added record.

@IDENTITY

It returns the last identity value generated for any table in the current session, across all scopes.
Let me explain this... suppose we create an insert trigger on table which inserts a row in another table with generate an identity column, then @@IDENTITY returns that identity record which is created by trigger.

SCOPE_IDENTITY
It returns the last identity value generated for any table in the current session and the current scope.
Let me explain this... suppose we create an insert trigger on table which inserts a row in another table with generate an identity column, then SCOPE_IDENTITY result is not affected but if a trigger or a user defined function is affected on the same table that produced the value returns that identity record then SCOPE_IDENTITY returns that identity record which is created by trigger or a user defined function.

IDENT_CURRENT
It returns the last identity value generated for a specific table in any session and any scope.
In other words, we can say it is not affected by scope and session, it only depends on a particular table and returns that table related identity value which is generated in any session or scope.

Example:

Using the below query I will explain the difference between this three

CREATE TABLE Table1(id int IDENTITY);

CREATE TABLE Table2(id int IDENTITY(100,1));

GO

CREATE TRIGGER Table1ins ON Table1 FOR INSERT

AS

BEGIN

   INSERT Table2 DEFAULT VALUES

END;

GO

--End of trigger definition

SELECT id FROM Table1;
--id is empty.

SELECT id FROM Table2;
--ID is empty.

--Do the following in Session 1
INSERT Table1 DEFAULT VALUES;
SELECT @@IDENTITY;
/*Returns the value 100. This was inserted by the trigger.*/

SELECT SCOPE_IDENTITY();
/* Returns the value 1. This was inserted by the
INSERT statement two statements before this query.*/

SELECT IDENT_CURRENT('Table2');

/* Returns value inserted into Table2, that is in the trigger.*/

SELECT IDENT_CURRENT('Table1');

/* Returns value inserted into Table1.
This was the INSERT statement four statements before this query.*/

-- Do the following in Session 2.

SELECT @@IDENTITY;

/* Returns NULL because there has been no INSERT action
up to this point in this session.*/

SELECT SCOPE_IDENTITY();

/* Returns NULL because there has been no INSERT action
up to this point in this scope in this session.*/

SELECT IDENT_CURRENT('Table2');

/* Returns the last value inserted into Table2.*/




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