1.Right click table and create table and create index A，B.
2.Right click the table and edit table
Right click the table and edit table again, there will be two edit window opened.
3.In the first edit window , delete the index A,B and click "ok".
4.After delete the index,in the second edit window ,add new index and then click "ok"
1.There will be an error window .
2.After delete all of the index and click "ok" ,it still has the error window.