Skip to Main Content
Troubleshooting Oracle Performance, Second Edition
book

Troubleshooting Oracle Performance, Second Edition

by Christian Antognini
June 2014
Intermediate to advanced content levelIntermediate to advanced
740 pages
23h 59m
English
Apress
Content preview from Troubleshooting Oracle Performance, Second Edition

SQL Statements with Strong Selectivity

To efficiently process SQL statements with strong selectivity, the data should be accessed through a rowid, an index, or a single-table hash cluster.1 These three possibilities are described in the next sections.

Rowid Access

The most efficient way to access a row is to directly specify its rowid in the WHERE clause. However, to take advantage of that access path, you have to get the rowid first, store it, and then reuse it for further accesses. In other words, it’s a method that can be considered only if a row is accessed at least two times. In practice, this is something that happens quite frequently when SQL statements have strong selectivity. For example, applications used to manually maintain data ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Troubleshooting Oracle Performance

Troubleshooting Oracle Performance

Christian Antognini
Oracle Wait Interface: A Practical Guide to Performance Diagnostics & Tuning

Oracle Wait Interface: A Practical Guide to Performance Diagnostics & Tuning

Richmond Shee, Kirtikumar Deshpande, K Gopalakrishnan
Expert Oracle Exadata, Second Edition

Expert Oracle Exadata, Second Edition

Martin Bach, Karl Arao, Andy Colvin, Frits Hoogland, Randy Johnson, Kerry Osborne, Tanel Poder

Publisher Resources

ISBN: 9781430257585Purchase book