ProcessDB实时/时序数据库——JAVA_API操作数据库对象

本文链接：https://blog.youkuaiyun.com/sun_race/article/details/127656137

一、数据库字段介绍

	int databaseId ; //数据库id

	String databaseName;//数据库名称

	byte    storagePolicy;//存储策略

	byte    storageRollPolicy;//滚动策略

	short   historyMaxSize;//历史表大小(默认1000)

	short   historyMaxInterval;//历史表最大时长(单位小时，默认30)

	short   historyMaxCount;//历史表最大个数(默认100)

	short   historyCacheMaxCount;//历史表每页最大缓存数(默认 20)

	short   historyPageCacheMaxCount;//历史表缓存页数(默认 10000)

	boolean isReffer ;// 是否引用库ID

	int   refferObjectId;//所引用的数据库ID

	String databaseDesc ; //数据库描述信息

    int createrId; //创建数据库的用户id

    int createTime; //数据库创建时间

二、创建新数据库

由于上篇文章已经介绍了如何连接ProcessDB数据库，这里就不过多赘述了，直接上代码

import com.processdb.connection.DBConnect;
import com.processdb.connection.DBConnectManager;
import com.processdb.connection.DBRoot;
import com.processdb.driver.common.ConnectInfo;
import com.processdb.driver.common.DatabaseInfo;
public class Test {
	 public static void main(String[] args) throws Exception
	    {
	    	ConnectInfo host = new ConnectInfo();
	    	host.setConnectName("instance01");
	    	host.setHostName("127.0.0.1");
	    	host.setHostPort(8301);
	    	host.setUserName("root");
	    	host.setPassword("root");
	    	host.setCacheable(false);
	    	DBConnect myConn = null;
			myConn = DBConnectManager.getInstance().getConnect(host);
			String databaseName = "D30";
			DBRoot root = DBRoot.getInstance(myConn);
			DatabaseInfo databaseInfo = new DatabaseInfo();
			databaseInfo.setDatabaseName(databaseName);
			int res = root.add(databaseInfo);
			if(res != 0)
			{
				System.out.print("Create database failed, error code: " + res);
				return;
			}
			else
			{
				System.out.print("Create database success.");
			}
}}

三、删除数据库

import com.processdb.connection.DBConnect;
import com.processdb.connection.DBConnectManager;
import com.processdb.connection.DBRoot;
import com.processdb.connection.DBase;
import com.processdb.driver.common.ConnectInfo;
public class Test {
	 public static void main(String[] args) throws Exception
	    {
	    	ConnectInfo host = new ConnectInfo();
	    	host.setConnectName("instance01");
	    	host.setHostName("127.0.0.1");
	    	host.setHostPort(8301);
	    	host.setUserName("root");
	    	host.setPassword("root");
	    	host.setCacheable(false);
	    	DBConnect myConn = null;
			myConn = DBConnectManager.getInstance().getConnect(host);
		    DBRoot root = DBRoot.getInstance(myConn);
			String databaseName = "D30";
			try {
			DBase dbase = root.getCachedDatabaseByName(databaseName);
			root.delete(dbase);
			System.out.print("Delete database success.");
			}catch (Exception e) {
				System.out.print("Delete database failed, error: " + e);
			}		
}}

四、修改数据库

import com.processdb.connection.DBConnect;
import com.processdb.connection.DBConnectManager;
import com.processdb.connection.DBRoot;
import com.processdb.connection.DBase;
import com.processdb.driver.common.ConnectInfo;
import com.processdb.driver.common.ConstantValue;
import com.processdb.driver.common.DatabaseInfo;
public class Test {
	 public static void main(String[] args) throws Exception
	    {
	    	ConnectInfo host = new ConnectInfo();
	    	host.setConnectName("instance01");
	    	host.setHostName("127.0.0.1");
	    	host.setHostPort(8301);
	    	host.setUserName("root");
	    	host.setPassword("root");
	    	host.setCacheable(false);
	    	DBConnect myConn = null;
			myConn = DBConnectManager.getInstance().getConnect(host);
			DBRoot root = DBRoot.getInstance(myConn);
			String dbName = "D30";
			DBase dBase = root.getCachedDatabaseByName(dbName);
			DatabaseInfo databaseInfo = dBase.getDatabaseInfo();
			//修改数据库的内容
			databaseInfo.setDatabaseDesc("HHHHH");
			//发起修改数据库请求
			int res = root.modifyDatabase(databaseInfo, ConstantValue.REQUEST_MODIFY );
			if(res != 0)
			{
				System.out.print("Update database failed, error code: " + res);
				return;
			}
			else
			{
				System.out.print("Update database success.");
			}
}}

五、查询数据库

import com.processdb.connection.DBConnect;
import com.processdb.connection.DBConnectManager;
import com.processdb.connection.DBRoot;
import com.processdb.connection.DBase;
import com.processdb.driver.common.ConnectInfo;
public class Test {
	 public static void main(String[] args) throws Exception
	    {
	    	ConnectInfo host = new ConnectInfo();
	    	host.setConnectName("instance01");
	    	host.setHostName("127.0.0.1");
	    	host.setHostPort(8301);
	    	host.setUserName("root");
	    	host.setPassword("root");
	    	host.setCacheable(false);
	    	DBConnect myConn = null;
			myConn = DBConnectManager.getInstance().getConnect(host);
			DBRoot root = DBRoot.getInstance(myConn);
			//通过名称获取数据库信息
			DBase dBase01 = root.getCachedDatabaseByName("PUBLIC");
			System.out.println("TEST01数据库的信息:");
			System.out.println("数据库ID："+dBase01.getID()+",名称："+dBase01.getName()
                                +",描述："+dBase01.getDesc());
}}

示例运行结果：

TEST01数据库的信息:
数据库ID：1001,名称：PUBLIC,描述：System database.

五、查询数据库列表

import java.util.Vector;
import com.processdb.connection.DBConnect;
import com.processdb.connection.DBConnectManager;
import com.processdb.connection.DBRoot;
import com.processdb.connection.DBase;
import com.processdb.driver.common.ConnectInfo;
public class Test {
	 public static void main(String[] args) throws Exception
	    {
	    	ConnectInfo host = new ConnectInfo();
	    	host.setConnectName("instance01");
	    	host.setHostName("127.0.0.1");
	    	host.setHostPort(8301);
	    	host.setUserName("root");
	    	host.setPassword("root");
	    	host.setCacheable(false);
	    	DBConnect myConn = null;
			myConn = DBConnectManager.getInstance().getConnect(host);
			DBRoot root = DBRoot.getInstance(myConn);
			root.loadAllDatabase();
			Vector<DBase> cachedDatabaseList = root.getCachedDatabaseList();
			System.out.println("该连接下的所有数据库：");
			for (DBase dBase : cachedDatabaseList) {
		   System.out.println("数据库名称："+dBase.getName()+",数据库描述："+dBase.getDesc()
           +",数据库ID："+dBase.getID());
			}
}}

示例运行结果：

该连接下的所有数据库：
数据库名称：TEST74,数据库描述：TEST007,数据库ID：1005
数据库名称：TEST01,数据库描述：TEST007,数据库ID：1002
数据库名称：TEST73,数据库描述：TEST007,数据库ID：1003
数据库名称：PUBLIC,数据库描述：System database.,数据库ID：1001
数据库名称：D20,数据库描述：HHHHH,数据库ID：1004