When you rename a table, the table name is automatically updated in every database diagram in which the table appears. It is updated in the database when you save the table or diagram.
Caution Think carefully before you rename a table. If existing queries, views, user-defined functions, stored procedures, or programs refer to that table, the name modification will make these objects invalid.
To rename a table
The table is renamed in the diagram as soon as you exit the Table name box.