言Oracle入门学习最常用的编程语言（oracle入门语）

Introduction

Oracle is a popular database management system used by organizations across the world. To make the most of this system, you need to learn the programming languages used with Oracle. In this article, we will discuss the most commonly used programming languages with Oracle and how to start learning them.

SQL: Structured Query Language

Structured Query Language or SQL is the most widely used language for querying databases. It is a standard language used for creating, manipulating and retrieving data from databases. With SQL, you can perform various operations on an Oracle database such as creating tables, inserting data, updating records, deleting data, and much more.

The syntax for SQL is simple and easy to understand. Here’s an example of how to create a table using SQL:

CREATE TABLE employee (

id INT,

firstname VARCHAR(20),

lastname VARCHAR(20)

);

This creates a table called ’employee’ with three columns – id, firstname, and lastname. The ‘INT’ datatype is used for the ‘id’ column, while ‘VARCHAR’ is used for the ‘firstname’ and ‘lastname’ columns.

PL/SQL: Procedural Language/Structured Query Language

PL/SQL is a procedural language used with Oracle databases. It is an extension of SQL that combines procedural programming with SQL’s data manipulation capabilities. With PL/SQL, you can write procedures, functions, and triggers that can be stored in the database and executed when needed.

Here’s an example of a PL/SQL program that adds two numbers:

DECLARE

a NUMBER := 10;

b NUMBER := 20;

c NUMBER;

BEGIN

c := a + b;

dbms_output.put_line(‘Sum is ‘ || c || ‘.’);

END;

This program declares two variables, ‘a’ and ‘b’, and assigns them the values 10 and 20, respectively. It then calculates the sum of these two numbers and stores the result in the variable ‘c’. Finally, it prints the result using the ‘dbms_output.put_line’ statement.

Java and Oracle

Java is a popular programming language used for developing applications and software. It is also used with Oracle databases to develop high-performance, scalable, and secure applications. Java can be used to access and manipulate Oracle databases using the JDBC (Java Database Connectivity) API.

Here’s an example of a Java program that inserts a record into an Oracle database:

import java.sql.*;

public class Mn {

public static void mn(String[] args) {

try {

// Connect to the database

Connection conn = DriverManager.getConnection(“jdbc:oracle:thin:@localhost:1521:XE”, “username”, “password”);

// Create the SQL statement

String sql = “INSERT INTO employee VALUES (101, ‘John’, ‘Doe’)”;

// Execute the statement

Statement stmt = conn.createStatement();

int rows = stmt.executeUpdate(sql);

// Print the number of rows affected

System.out.println(rows + ” rows affected.”);

// Close the connection

conn.close();

} catch (Exception e) {

System.out.println(e.getMessage());

}

}

}

This program connects to an Oracle database, creates an SQL statement that inserts a record into the ’employee’ table, and executes the statement. The number of rows affected is then printed to the console.

Conclusion

Learning the programming languages used with Oracle is essential for anyone working with this popular database management system. SQL is the primary language used for querying databases, while PL/SQL is used for creating stored procedures, functions, and triggers. Java is a popular programming language used to develop applications and software that interface with Oracle databases. With these languages in your toolkit, you can make the most of Oracle and build efficient, scalable, and secure applications.