>I have two identical tables. I want to transfer data from one to another.
>I want to know if a it exists a stored procedure or a command in SQL to do that, or if a have to prepare my own stored procedure. I already checked
>the Import/Export Data possibility but it seems from a database to another
>database. My both tables are in the same database... Thank you for your help.

If the user where the source table allows selects from the other user table, there is a SQL. Keep in mind I am using Oracle, so translate the the SQL Server equivalent:

insert into mytable (select * from otheruser.mytable);

This assumes identical table structure and no Long [raw] data type fields. You can also include a where clause in the sub-query.