The drop index command removes an index from the database, reclaiming their storage space
The drop index command cannot be used on any of the system tables in the master database or in the user database.
You might want to drop an index if it is not used for most or all of your queries.
For example, to drop the index phone_ind in the friends_etc table:
drop index friends_etc.phone_ind
Use sp_post_xpload to check and rebuild indexes after a cross-platform load database where the endian types are different.