Identity Insert- error message - sql-server

Question

Getting the following error: (line 21 is declare statement).
Msg 544, Level 16, State 1, Procedure insert_employee_details, Line 21
Cannot insert explicit value for identity column in table 'DB_Actions' when IDENTITY_INSERT is set to OFF.
Here is what I have tried:
SET IDENTITY_INSERT DB_Actions ON;
But then I get this error:
Msg 8107, Level 16, State 1, Line 31
IDENTITY_INSERT is already ON for table 'StacysDB.dbo.Employee_Details'. Cannot perform SET operation for table 'DB_Actions'.
This doesn't makes to sense to me. First it doesn't work because identity insert is off. Then when I try to turn it on it says its already on.
I know this is a common error so I tried a confirmed solution by re-creating the table and setting identity insert to on before inserting the values, and then back to off and inserting the values, but i got the same error (Msg 8107).
Thanks for any help.
--1
--CREATE TABLE DB_Actions
--(
--Id numeric(5,0) IDENTITY(1,1) PRIMARY KEY,
--Table_Name varchar(20),
--Action_Name varchar(10),
--User_Name varchar(50),
--Done_ON datetime,
--Record_Id numeric(5,0)
--);
--2
--INSERT TRIGGER
--CREATE TRIGGER insert_employee_details
--ON Employee_Details
--FOR INSERT
--AS
--DECLARE #id int, #name varchar(20)
--SELECT #id = Emp_Id, #name = Emp_First_Name FROM inserted
--INSERT INTO DB_Actions(Id, Table_Name, Action_Name, User_Name,
--Done_ON, Record_Id)
--VALUES(#id,
-- 'Employee_Details',
-- 'INSERT',
-- #name,
-- getdate(),
-- #id
--);
INSERT INTO Employee_Details(Emp_Id, Emp_First_Name, Emp_Middle_Name, Emp_Last_Name, Emp_Address1, Emp_Address2, Emp_Country_Id, Emp_State_Id, Emp_City_Id, Emp_Zip, Emp_Mobile, Emp_Gender, Desig_Id, Emp_DOB, Emp_JoinDate, Emp_Active)
VALUES(9000, 'A', 'B', 'C', 'D', 'E', 2, 3, 4, 44444, 4444444, 1, 3333, getdate(), getdate(), 0);

Answer 1

IDENTITY_INSERT option is not meant to be used in your day-to-day processing. IDENTITY_INSERT is only meant as temporary workaround. For example, you need to restore values that were accidentally deleted. If you have to insert explicit values into identity field as part of your regular processing, you have to rethink your solution.
The easiest way to achieve this is to store explicit values in another field and leave identity to SQL server to manage. In your solution this would mean removing DB_Actions.ID field from the trigger insert statement (you are already storing ID in record_id).
Also, inserted table can return more than one record, so you should not try to store that in a single variable. Instead insert using a select statement. This will also make your code more readable.
So, change your trigger as follows to resolve the issue:
CREATE TRIGGER insert_employee_details
ON Employee_Details
FOR INSERT
AS
INSERT INTO DB_Actions(Table_Name, Action_Name, User_Name, Done_ON, Record_Id)
SELECT 'Employee_Details', 'INSERT', Emp_First_Name, getdate(), Emp_Id
FROM inserted;
If you are on SQL Server 2012 or later, alternative solution would be to use SEQUENCE object instead of identity. SEQUENCE gives you more flexibility and resolves a lot of issues with identity property.
Note also that User_Name field in DB_Actions is probably meant for the system user performing the action, rather than the employee name from the table (you can always get the latter by querying the original table with the record id). So instead of Emp_First_Name field consider using USER_NAME() built in function.