The CREATE INDEX can specify Omnidex indexes. Typically, Omnidex indexes are specified in the CREATE TABLE statement for ease of maintenance.
CREATE <OMNIDEX | QUICKTEXT | FULLTEXT | CUSTOM | NATIVE> INDEX [[(owner)]table.]index [ON table_spec] (<column | substring> [, <column | substring>…] )] [KEYWORDING] [PROXIMITY] [<CASE_INSENSITIVE | CASE_SENSITIVE>] [STANDALONE] [BITMAP] [EXCLUDED_WORDS] [PHONETIC] [PREJOIN table] [<RECORD_SPECIFIC | RECORD_COMPLEX>]] IN “filename” [WITH options]