Oracle/SQL Tutorial for Beginners in PDF

Content

• SQL Structured Query Language
• SQL*Plus (Minimal User Guide, Editor Commands, Help System)
• Oracle Data Dictionary
• Application Programming
• Integrity Constraints and Triggers
• System Architecture

Learning the Oracle/SQL Tutorial

The Oracle data dictionary is among the essential parts of the Oracle database management system (DBMS). It stores all the information pertaining to the structures and objects of the database, such as the tables, columns, users, and data files, among other things. In this tutorial, we'll use the terms "table", row, and "column" to denote relationships, tuples, and attributes. Table, row, and column are all terms used in SQL to refer to relations, tuples, and attributes, respectively. PL/SQL is an extension of Oracle-SQL that is procedural and provides constructs analogous to those found in imperative programming languages. Users and designers can create sophisticated database applications with the help of PL/SQL. These applications need control structures and procedural elements such as procedures, functions, and modules.

Increasing the expressiveness of SQL and lowering the cost of maintaining and modifying applications are two of the primary objectives of the PL/ML programming language. An area of the computer's main memory is set aside for use as a database file each time the Oracle DBMS server is used to launch a new database. The shared pool, the database buffer, and the redo-log buffer are the components that make up the SGA. When multiple users connect to the same instance simultaneously, the shared memory area (SGA) is shared among all of those users. The server is in charge of handling all database activities, such as running SQL statements, managing users, managing resources, and managing storage, among other things.

A cache that is used to hold the data blocks that have been read from data files is known as the database buffer. Oracle uses an algorithm known as least recently used, or LRU, to manage the space available in the database buffer. The portion of the SGA known as the "shared pool" is the component that every user utilizes. Take note that gaining access to the data dictionary is a prerequisite for running any SQL statement. The log-archive buffer (optional) and the Program Global Area are additional storage structures that can be found in the computer's primary memory (PGA).

There is no set number of processes because it depends on the instance's configuration. Oracle processes are typically run in the background and are responsible for carrying out I/O operations while the database is being run.