Can someone explain me how the range scan is better than Skip Scan in Oracle 9i.
Is it advantage of tuning queries to take RANGE SCAN access path than SKIP SCAN path?

In index range scans,
< quotedoc>

Multiple rows with identical values are sorted in ascending order by rowid.
< /quotedoc>

in Skip scan
< quotedoc>

Skip scanning lets a composite index be split logically into smaller subindexes. In skip scanning, the initial column of the composite index is not specified in the query. In other words, it is skipped.

The number of logical subindexes is determined by the number of distinct values in the initial column. Skip scanning is advantageous if there are few distinct values in the leading column of the composite index and many distinct values in the nonleading key of the index.
< /quotedoc>

My understanding is,
Skip scanning is good only if the cardinality of the leading columns are low ( very few distinct records).
if the cardinality of the rest columns are too low, eventually the CBO will ignore the indexes.

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