Does mysqldump --no-tablespaces dumps index files of InnoDB? I know that MyIsam uses separate index files *.MYI for index. So if one uses mysqldump with --no-tablespaces, does that mean index is not exported?
"Tablespaces" are for clumping tables into a single
.ibd. The mysqldump options relating to that control whether to output the DDL statements such as
mysqldump does not dump the contents of indexes, regardless of Engine. It does dump the definitions of the indexes. When reloading, the indexes will be recreated. Yes, MyISAM has a separate file for indexes while InnoDB includes the indexes in the same "tablespace" file; but the locations of indexes is an implementation detail that does not matter when dumping and reloading tables.
If you have not explicitly created any "tablespaces", ignore options relating to them. (Very few people use tablespaces.)