Two Methods for SQL server to obtain the new record ID column Value

For newly added records, you can obtain the value of the Automatic Identification column for the new record in two ways:
1. Use the OUTPUT keyword in INSERT
Insert into table_name (column1, column2, column3)
Output inserted. ID -- return the Automatically increasing value of the ID column
VALUES ('','','')

-- ADO. NET call
Int r = command. ExecuteScalar ();

2. Use global variable @ IDENTITY global variable
Insert into table_name (column1, column2, column3)
VALUES ('','','')
SELECT @ IDENTITY AS ID

-- ADO. NET call (two statements are executed together)
Int r = command. ExecuteScalar ();