>>>> well, how I know what are the index of one table ?????
answer:
option 1) dbschema -d <you_database> -t <your_table> -ss
option 2) open a connection with your database and write a SQL with tables "systables" and "sysindexes" or "sysindices"
>>>> How can I rebuild one index for one table ?
option 1) drop index...; create index...
option 2) set indexes <idx_name> disabled; set indexes <idx_name> enabled