【openGauss3.0.0之Java API基本操作】

一、环境说明

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1. 虚拟机VMWareWorkstation15+
2. JDK1.8+
3. Maven
4. IDEA

二、创建新的数据库用户

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1. 使用omm用户登录虚拟机，并登录openGauss

   gsql -d postgres -p 15400
   

2. 创建数据库新用户如suben

   create user suben
   grant all privileges to suben
   

3. 创建数据库如suben_db01

   create database suben_db01 owner suben;
   

三、添加客户端IP至pg_hba.conf

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1. 查看本机IP地址,cmd执行ipconfig
   

2. 使用omm用户编辑pg_hba.conf，将客户端（本机）IP地址添加至其中

   vim /opt/huawei/install/data/dn/pg_hba.conf
   

   

3. 重启openGauss服务

   gs_om -t stop
   gs_om -t start
   

四、编写程序测试

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1. 创建maven
2. 添加openGauss数据库驱动依赖

    <dependency>
           <groupId>org.opengaussgroupId>
           <artifactId>opengauss-jdbcartifactId>
           <version>3.0.0version>
       dependency>
   

3. 编写程序，实现数据库表的简单操作

   import java.sql.*;
   import java.util.Properties;
   
   public class OpenGaussDemo {
       public static void main(String[] args) throws Exception {
           Connection conn = getConnect("suben_db01","suben","Gauss_123");
           // 创建表
           //createTable(conn,"create table test01(id int,name varchar(10))");
           // 插入数据
           // insert(conn,"insert into test01 values(1,'苏江明')");
           // 查询数据
           // select(conn,"select * from test01 where id=1","id","name");
           selectDynamicParameter(conn,"1","id","name");
   
       }
   
       public static Connection getConnect(String db,String user,String pwd) {
           String driver = "org.opengauss.Driver";
           // 需要创建新的数据库用户，使用新的数据库用户连接
           String sourceURL = "jdbc:opengauss://192.168.76.150:15400/"+db+"?";
           Properties properties = new Properties();
           properties.setProperty("user",user);
           properties.setProperty("password",pwd);
           Connection conn = null;
           try {
               Class.forName(driver);
           } catch (Exception var9) {
               var9.printStackTrace();
               return null;
           }
           try {
               conn = DriverManager.getConnection(sourceURL,properties);
               System.out.println("连接成功！ ");
               return conn;
           } catch (Exception var8) {
               var8.printStackTrace();
               return null;
           }
       }
   
       public static boolean createTable(Connection conn,String sql) throws SQLException {
           Statement statement = conn.createStatement(); 容易产生SQL注入
           return statement.execute(sql);
       }
   
       public static boolean insert(Connection conn,String sql) throws SQLException {
           Statement statement = conn.createStatement();
           return statement.execute(sql);
       }
   
       public static void select(Connection conn,String sql,String... cols) throws SQLException {
           PreparedStatement preparedStatement=conn.prepareStatement(sql);
           ResultSet resultSet=preparedStatement.executeQuery();
           while (resultSet.next()){
               System.out.println(resultSet.getObject(cols[0])+" "+ resultSet.getObject(cols[1]));
           }
           if (preparedStatement != null){
               preparedStatement.close();
           }
           if (conn != null){
               conn.close();
           }
       }
   
       public static void selectDynamicParameter(Connection conn,String... cols) throws SQLException {
           PreparedStatement preparedStatement=conn.prepareStatement("select * from test01 where id=?");
           preparedStatement.setObject(1,Integer.valueOf(cols[0]));
           ResultSet resultSet=preparedStatement.executeQuery();
           while (resultSet.next()){
               System.out.println(resultSet.getObject(cols[1])+" "+ resultSet.getObject(cols[2]));
           }
           if (preparedStatement != null){
               preparedStatement.close();
           }
           if (conn != null){
               conn.close();
           }
       }
   }
   
   

   到此，已经简单完成了使用Java api实现连接openGauss数据库、创建表、插入数据、查询数据等操作。您也尝试下吧！如对您有用，欢迎给博主点点赞~~~~~