Chapter 3 Logical Database Layouts Database Processing Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Optimal Flexible Architecture image source: Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts OFA The OFA standard is a set of configuration guidelines for fast, reliable Oracle databases that require little maintenance. At the highest level, it is designed to logically separate objects by object type and activity type. It is the structure you get if you create a default database Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts System tablespace At a minimum you have to have a SYSTEM tablespace It would be a very poor design to put all objects into one tablespace. –Data dictionary should be isolated Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Data tablespaces Our author suggests that data tablespaces should be organized by application The data for each application should isolated from the system tables and other tablespaces –For example, human resources, accounting, sales, inventory management –One database, many applications Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Index tablespaces Because of concurrent I/O, indexes should be stored separately from their associated tables. In my installation, my assumption was that the indexes would be in the indx01.dbf file I queried the dba_indexes view and found... Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Index tablespaces Chapter 3 - OFA Primary Key indexes in User tablespace

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Index tablespaces Chapter 3 - OFA USER tablespace is in the USERS01.DBF file.

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Index tablespaces Chapter 3 - OFA So I moved it...

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Index tablespaces Chapter 3 - OFA And now it’s in the index data file

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Tools tablespaces Used to store tables created by Oracle or 3rd party tools (applications) that create tables owned by the SYSTEM account Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts User tablespaces For development projects All other tables should be created by the DBA Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts Other tablespaces RBS Temp Chapter 3 - OFA

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 3 - Logical Database Layouts OFA Further divide the previous tablespaces into pairs of high/low usage tablespaces Common-sense Logical Layouts –Segment types that are used in the same way should be stored together –The system should be designed for standard usage –Separate areas should exist for exceptions –Contention among tablespaces should be minimized –The data dictionary should be isolated Chapter 3 - OFA