Oracle development practical learning

Oracle development practical learning

Middleware: A component that decouples specific business and underlying logic.

Chapter 1 Oracle Relational Database

operation:

(1) What are relational models and relational databases.

Relational database: Relational database system is currently the most widely used database system. It uses relational data model as the way of data organization.

Relational model: self-understanding: The relational database model is improved in terms of the constraints of the hierarchical structure, without completely giving up the hierarchical structure, we can directly access any table. No need to access all parent objects, any table can be connected,

(What is a hierarchical database model? The hierarchical database model is an inverted tree state structure. The tables of this model have a child-parent relationship. Each child table has a parent table. The child table is completely dependent on the parent table. Any record in the child table has only (Only when the corresponding parent table item exists in the parent table)

(2) What types of databases are there.

Self-understanding:

1. Mainly non-relational database NoSQL (NoSQL = Not Only SQL), which means "not just SQL". Non-relational database: A data storage system that is non-relational, distributed, and does not follow the ACID principles.

2. Relational database: It is a database built on the basis of a relational model. It uses mathematical concepts and methods such as set algebra to process data in the database.

3. relational database

⚫ MySQL
⚫ MariaDB (alternative to MySQL, English Wikipedia switched from MySQL to MariaDB)
⚫ Percona Server (alternative to MySQL)
⚫ PostgreSQL
⚫ Microsoft Access
⚫ Microsoft SQL Server
⚫ Google Fusion Tables
⚫ FileMaker
⚫ Oracle database
⚫ Sybase
⚫ dBASE
⚫ Clipper
⚫ FoxPro
⚫ foshub

2. Non-relational database (NoSQL)

⚫ NoSQL
⚫ BigTable (Google)
⚫ Cassandra
⚫ MongoDB
⚫ CouchDB
⚫ key-value (key-value) database
⚫ Apache Cassandra (used by Facebook): highly scalable
⚫ Dynamo
⚫ LevelDB (Google)

(3) Explain the normalization theory of the database.

Chapter 2 Oracle Database Architecture

2.1 Oracle's physical storage structure

Oracle's physical storage structure is composed of operating system files stored on disks, and Oracle needs to use these files at runtime.

4 Generally, an Oracle database is physically composed of three types of files, which are data files ( .dbf), control files ( .ctl) and redo log files (*.log).

2.2 Oracle's logical storage structure

2.3 Oracle process structure

When the Oracle database is started, multiple Oracle background processes are started. The background processes are executable code blocks used to perform specific tasks. After the system is started, different tasks are performed asynchronously for all database users.

By querying the data dictionary v$bgprocess, you can understand the background process information started in the database.

2.4 Oracle memory structure

Is one of the main factors affecting database performance,

2.6 Data Dictionary

The data dictionary is a set of tables automatically created and updated by Oracle. It is an important part of the Oracle database and provides information about the database structure, database object space allocation, and database users.

4 The owner of the data dictionary is the sys user, and the data dictionary tables and data dictionary views are stored in the system tablespace.

Chapter 3 Applicable SQLPLus Tools

Chapter 4 Managing Table Spaces

Chapter 5 Schema Objects

Chapter 6 Management Control File and Log File

Chapter 7 SQL Language Fundamentals

Chapter 8 Subqueries and Advanced Queries

Chapter 9 PL/SQL Basics

Chapter 10 Stored Procedures, Functions, and Triggers

Chapter 11 Other Table Types

Chapter 12 User Rights and Security

Chapter 13 SQL Statement Optimization

Chapter 14 Data Loading and Transmission

Chapter 15 Using RMAN Tools

Chapter 16 Oracle DataBase 11g Flashback Technology