Steps:
1.Go to transaction SE11, enter the table/structure name. Click on change.
2.Go to Edit->Transfer Fields.
3.Below pop up window will appear. Enter the table/structure name and click on “Selection” if you want to select specific fields or click “Copy All” if you want to copy all fields of the table/structure.
4. Select the fields and click copy.
5.Below message will appear at eth status bar.
6.Put a cursor where you want to copy the fields and click paste as below or right click and paste.
7.Here the Key and Initial Values also copied. So change it as per the requirement.
