1. Introduction of Week 6 Assignment Discussion
2011 Fall
Assignment Discussion
Graded (DBMS installation):
hardware requirements, open .ISO file
Installation steps
Lessons Learned: error, documentation, instruction manual, need more info
Turned in: (Creation of Database)
Due this week: 5-1 (Connectivity Paper)
Review of previous week and module
Database Connectivity: ODBC, JDBC
Oracle Connectivity and Network: listener, naming method
Module 2: Database Installation and Configuration
Overview of this week
Database access and metadata review
Database Change Management
Availability Requirement and Architecture
ITEC 450

2. Access Database – SQL Plus
2011 Fall
ITEC 450

3. SQL Plus Login
2011 Fall
ITEC 450

4. SQL Plus Commands
2011 Fall
ITEC 450

5. OEM (https://{hostname}:1158/em)
2011 Fall
ITEC 450

6. Module 3 Database Management
2011 Fall
Module 3 Database Management
ITEC 450
Section 1 Database Change Management

7. Drivers for Change Management
2011 Fall
Change is inevitable but necessary for business survival and success.
Missed a requirement – an existing system is missing a feature
Identified a defect
Scalability demand, marketplace changes
Policy and politics – process, procedure or methodology; legislation changes
ITEC 450

8. Change Management Requirements
2011 Fall
Proactively change – the earlier to make change, the lower cost to achieve it
Planning analysis – intelligently examining the change whether it is necessary, and planning to do it right the first time
Impact analysis – comprehensive impact and risk analysis
Execution – standardization of procedure, availability consideration, quick and efficient delivery
ITEC 450

9. Types of Database Changes
2011 Fall
DBMS software – versions and releases for new features, functions, bug fixes, support models
Hardware configuration – memory, CPU, storage device
Logical and physical design for an application
Physical database structures
ITEC 450

10. Impact of Database Changes
2011 Fall
Data Definition Language is mainly used for database changes.
Create, alter, and drop schema objects require exclusive access to the specified object
The change is implicitly committed
The change may cause dependent objects become invalid, which may need to recompile or reauthorize schema objects
Recovery from a database change is challenging, and has to be well-planned.
ITEC 450

11. Execution of Database Changes
2011 Fall
Maintain current database structures – source control and version control
Migration process
Request database change
Standardized change requests
Managing database changes from one database environment to another
Condense a series of changes by comparing database structures, and migrate the differences
ITEC 450

12. Examples of Database Changes
2011 Fall
Change Management: planning (necessary?) impacts, and execution (recovery?)
Add a new column to the end of a table
Resize a column from char (8) to char (12)
Re-create a new package, procedure, or function
Add a new column to the middle of a table
ITEC 450

13. Module 3 Database Management
2011 Fall
Module 3 Database Management
ITEC 450
Section 2 High Availability Requirement and Architecture

14. Drivers of Availability
2011 Fall
Availability is the condition where a given resource can be accessed by its consumers.
Mandate for 24x7 availability
Shrinking maintenance window
Full-time availability: airline reservation systems, credit card approval
Cost of downtime
ITEC 450

15. Availability Problems
2011 Fall
Disasters: loss of the data center
System failures
Server infrastructure problems: network , loss of the server hardware, storage, operating system
Software failure: DBMS, application, corruption of data
Data failures
Procedure problems: security and authorization, loss of database objects
Human errors: loss of data, DBA mistakes
ITEC 450

16. Availability Solutions
2011 Fall
Automate DBA functions
Exploit high-availability DBMS features
Exploit clustering technology
Hardware redundancy design
ITEC 450

17. High Availability DBMS Features
2011 Fall
Solutions to disasters
Oracle data guard – a single primary database and one or more standby database
SQL Server database mirroring – a single copy of the mirrored database that must reside on a different server instance, usually on a separate physical server in a different location
Hardware replication: EMC SRDF
Solutions to system failures
Oracle Real Application Clusters
SQL Server transactional replication
DB2 Data Sharing
Solutions to data failures
Backup and recovery capability
Flashback database: view data at a point-in-time in the past
Partition: decompose large tables and indexes into smaller and more manageable pieces
ITEC 450

18. Clustering Technology
2011 Fall
A cluster is a group of interconnected servers for increasing the reliability of servers. Oracle standby database:
ITEC 450

19. SQL Server Database Mirroring
2011 Fall
Database mirroring maintains an exact copy of the database on the mirror. It works at the level of the physical log record (by sending the actual log records to the mirror server).
ITEC 450

20. SQL Server Transactional Replication Architecture
2011 Fall
ITEC 450

21. Oracle Real Application Cluster (RAC)
2011 Fall
Oracle database with RAC architecture build higher levels of availability on top of the standard Oracle features.
ITEC 450

22. Hardware Redundancy Design
2011 Fall
No single point of failures on CPU, Memory, I/O controller, Network, etc.
Clustered software to failover to another server in seconds
RAID technology (Redundant Arrays of Inexpensive Disks) – one large logical storage unit with a set of physical disk drives
ITEC 450

23. RAID Technology
2011 Fall
RAID example with 4 disks and striping. Pages 1-4 can be read/written simultaneously
ITEC 450

24. Wrap Up Assignment 6-1: Research Paper: Database High Availability
2011 Fall
Assignment 6-1: Research Paper: Database High Availability
ITEC 450