I work on Oracle systems where I two type of indices exists in any table:
- Unique index (Based on any search key which is unique key).
- Normal index (Index made on any search key which is not candidate or primary key).
But now I came to know about two new type of indices from a university documentation:
- Primary index
- Secondary index
How are primary and secondary indices different from each other? Are they the same as unique and normal index respectively in Oracle?
I also want to know about below two indices:
- Dense index
- Sparse index
Can we consider dense and sparse indices as type of primary and secondary indices?