título: JAVA usa JDBC para conectarse a la versión básica de la base de datos ORACLE
fecha: 2023-08-17
categorías:
- Etiquetas de base de datos
: - base de datos
- Resumir
- Oráculo
- jdbc
JAVA usa JDBC para conectarse a la versión básica de la base de datos ORACLE
JAVA usa JDBC para conectarse a la versión básica de la base de datos ORACLE
JAVA usa JDBC para conectarse a la base de datos ORACLE para mejorar y optimizar la versión
Optimización de fábrica de compilación JAVA usa JDBC para conectarse a la base de datos ORACLE
La conexión jdbc de la base de datos se divide en varios pasos
dependencia del oráculo de maven
<dependency>
<groupId>com.oracle.database.jdbc</groupId>
<artifactId>ojdbc6</artifactId>
<version>11.2.0.4</version>
</dependency>
1. Cargue el controlador
Class.forName(driver);
2. Enlace a la base de datos
//连接数据库的地址,用户名和密码
String url = "jdbc:oracle:thin:@localhost:1521:orcl1";
String name = "hr";
String pass = "orcl";
conn = DriverManager.getConnection(url,name,pass);
3. (la declaración define el objeto de la declaración, declaración sql)
Statement st = con.createStatement();
//定义一个sql语句
String sql = "select department_id,department_name,location_id from departments";
4. Ejecute la declaración sql.
ResultSet rs = st.executeQuery(sql);
5. Llame al método del conjunto de resultados para lograr el recorrido.
while(rs.next()){
//获得结果集的数据,下标从1开始,1表示一行第一列,2表示第二列
int id = rs.getInt(1);
String name = rs.getString(2);
String pass = rs.getString(3);
System.out.println("部门号是:"+id+" 部门名是:"+name+" 部门所在地是:"+pass);
}
6. Cerrar recursos
rs.close();
ps.close();
conn.close();
el caso
Clase de atributo de departamento
package vo;
public class Department {
private int departmentId;
private String departmentName;
private int manager_id;
private int location_id;
public int getDepartmentId() {
return departmentId;
}
public void setDepartmentId(int departmentId) {
this.departmentId = departmentId;
}
public String getDepartmentName() {
return departmentName;
}
public void setDepartmentName(String departmentName) {
this.departmentName = departmentName;
}
public int getManager_id() {
return manager_id;
}
public void setManager_id(int manager_id) {
this.manager_id = manager_id;
}
public int getLocation_id() {
return location_id;
}
public void setLocation_id(int location_id) {
this.location_id = location_id;
}
public String toString(){
return "id:"+departmentId+" name:"+departmentName;
}
}
DepartmentsDao define jdbc y pruebas
package dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import vo.Department;
public class DepartmentsDao {
//实现连接数据库查询所有的部门信息
public void getAllDepartments(){
try {
//连接数据库的地址,用户名和密码
String url = "jdbc:oracle:thin:@localhost:1521:orcl1";
String name = "hr";
String pass = "orcl";
//1,加载数据库驱动
Class.forName("oracle.jdbc.driver.OracleDriver");
//2,获得连接
Connection con = DriverManager.getConnection(url, name, pass);
//3定义语句对象
Statement st = con.createStatement();
//定义一个sql语句
String sql = "select department_id,department_name,location_id from departments";
//4,执行sql语句,查询
ResultSet rs = st.executeQuery(sql);
//调用结果集的next方法实现遍历
while(rs.next()){
//获得结果集的数据
int id = rs.getInt("department_id");
String dname = rs.getString("department_name");
int lid = rs.getInt("location_id");
System.out.println(id+" "+dname+" "+lid);
}
//5,关闭资源
rs.close();
st.close();
con.close();
}
catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//根据id和名字查询信息
public Department getDepartmentById(int id,String departmentName){
Connection con = null;
Statement st = null;
ResultSet rs = null;
try {
//连接数据库的地址,用户名和密码
String url = "jdbc:oracle:thin:@localhost:1521:orcl1";
String name = "hr";
String pass = "orcl";
//1,加载数据库驱动
Class.forName("oracle.jdbc.driver.OracleDriver");
//2,获得连接
con = DriverManager.getConnection(url, name, pass);
//3定义语句对象
st = con.createStatement();
//定义一个sql语句
String sql = "select * from departments where department_id="+id+" and department_name='"+departmentName+"'";
//4,执行sql语句,查询
rs = st.executeQuery(sql);
//调用结果集的next方法实现遍历
if(rs.next()){
Department d = new Department();
d.setDepartmentId(rs.getInt(1));
d.setDepartmentName(rs.getString(2));
d.setManager_id(rs.getInt(3));
d.setLocation_id(rs.getInt(4));
return d;
}
}
catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
try {
rs.close();
st.close();
con.close();
}
catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return null;
}
public static void main(String[] args) {
// TODO Auto-generated method stub
DepartmentsDao dao = new DepartmentsDao();
//dao.getAllDepartments();
Department d = dao.getDepartmentById(60, "IT");
System.out.println(d);
}
}