Indexes and Performance - opracowanie

Indexes and Performance
Indexes generally improve the performance of queries and DML statements that
operate on a single, existing row or a small number of existing rows. However, too
many indexes can increase the processing overhead for statements that add, modify,
or delete rows.
See Also:
■ "About Tables" on page 8-5
See Also:
■ "Viewing Indexes" on page 8-22
■ "Example: Creating an Index" on page 8-22
■ Oracle Database Concepts
Managing Indexes
Managing Schema Objects 8-21
Before you add additional indexes, examine the performance of your database for
queries and DML. You can then compare performance after the new indexes are
added.
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