Explanation:
A workspace is a virtual database facility that enables you to maintain multiple versions of one row of data and it enables each workspace context to reference a different version of this row as compared to another workspace context. It’s possible to create workspace if there is no versionenabled table in the database.
Incorrect Answers:
1: The unit of versioning is the table, not the schema.
2: It is not possible to version enable a table in SYS schema.
3: This statement about the same amount of segments as versions for the same base table is incorrect.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 168-176
Chapter 3: Manageability Enhancements

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