Database Administrator tasks

I. jobs of the database administrator
Generally, as a DBA, do the following 12 tasks
Installation and configuration
Capacity Planning
Application Architecture Design
Manage database objects
Bucket Management
Security Management
Backup and recovery
Performance monitoring and Tuning
Job Scheduling
Network Management
High availability and high scalability Management
Troubleshooting

The following describes in detail the specific content of each task:

Task 1: installation and configuration

Build a good environment, whether installed or configured, should be based on actual needs, so that the system meets the user's actual needs.

Task 2: Capacity Planning

It refers to a general plan for the entire Oracle Database 10 Gb system, mainly to solve the bottleneck problem. Specific considerations include hardware capacity planning, software planning, and network planning. From the perspective of term, we should consider short-term, medium-term, and long-term planning. Short-term planning aims to address the current daily needs. The medium-term planning mainly aims to meet the development needs. Long-term planning is mainly to meet extreme needs.

Task 3: Application Architecture Design

Application architecture design includes database design, application design, and corresponding technical architecture design.
The Database Design considers the logic requirements of the database, the database creation method and quantity, and the storage location of database data files and log files. Two ways to create a database: automatically create a database after the 10 Gb Oracle database system is successfully installed, or use the database configuration Assistant (dbca) tool to create a database.
The application design should consider the selection of development tools, API technology, the combination of internal resources and external resources, and the distribution of application architecture.

The technical architecture design includes the presentation layer, logic layer, and data layer distribution.

Task 4: manage database objects

Managing database objects is the most basic and important task of using databases. These objects include tables, indexes, views, processes, functions, packages, triggers, sequences, synonyms, and so on. To manage database objects, DBA should answer the following questions:
What data should the system contain?
How should we store this data?
What tables should be created in the system?
What indexes should be created in these tables to accelerate the retrieval of these table data?
Should I create a view? Why create these views?
What processes should be created, functions, and packages?
On which tables should I create a trigger? What are the types of these triggers?
Should I create a synonym?

Task 5: bucket Management
Bucket management includes data allocation space, which can meet the requirement of continuous data growth. To manage a bucket, DBAs need to understand the following issues:
What files does the current database consist?
How should I set the size of the redo transaction log?
How fast is data growth?
How can I configure the growth rate of table space?
When can data in the database be cleared or transferred to another place?

Task 6: Security Management
Security management includes account management and permission management.

Task 7: backup and recovery
Formulate and implement backup and recovery policies. Backup is to make copies of data, and recovery is to restore copies of data to the system.

Task 8: Performance Monitoring and Tuning
With the help of some tools and performance indicators, You can monitor the operation of the system. If some operation indicators have problems, DBAs should promptly take remedial measures to keep the system running efficiently.

Task 9: Job Scheduling
Oracle Database 10 Gb provides many automatic tools. DBAs should make full use of these tools and mechanisms and answer the following questions:
Which jobs should be scheduled by the system?
When should these jobs be executed?
How can we ensure that these jobs can be correctly executed?
What should I do if the execution of the automatically executed job fails?
How can the system perform operations in a balanced manner?

Task 10: Network Management
As a grid database, network management is more important. Oracle Database 10 Gb provides many network management tools and services, and DBA should use these tools and services to plan and manage network operations. In order to do a good job in network management, DBA should be able to answer the following questions:
How to define database connections?
Are dedicated servers or shared servers used?
How to use Oracle Net Listener?
How to Use the Oracle configuration file?
How can I work in a multi-layer network environment?

Task 11: high availability and high scalability Management
As a DBA, the system must be highly available and scalable. Availability is an indicator that measures the normal running time of a computer system. Scalability describes the number of concurrent user accesses that an application can accept.

Task 12: troubleshooting
DBAs should quickly diagnose, accurately judge, and quickly fix the problem. DBA is a professional doctor of database systems.

II Architecture
The architecture of the Oracle system refers to the relationship between the main components of the Oracle system and these components and the way they work.
The architecture of Oracle mainly involves the following five components:
The ability to connect to database instances, which is a way of working collaboratively in the Oracle system architecture;
Server process;
The structure level of the file system;
Memory area management, especially the features and functions of the system global area (SGA;
Background process.
The following details:
Connect to a database instance
User process: it can be seen as software that tries to connect to the database, such as a customer tool. User processes can use Oracle Net Services (Oracle network service) to communicate with databases. Oracle Net Services is a group of components that provide network connections through the network connection protocol. For application developers and data administrators, Oracle Net Services shields the complexity of setting different networks on different hardware platforms.
The Oracle listener (listener) is a process running on the Oracle database server. It monitors connection requests from the customer's applications.
Oracle network customers: SQL * Plus, Oracle Enterprise Manager, and Oracle Net manager can use Oracle Net Services Customer adapters to interact with Oracle databases.