【Oracle/Java】批量删除16张十万数据的表 单线程耗时45秒 多线程耗时38秒

昨天做了插入的单线程多线程比较，今天做个删除的。

单线程批量删除类代码：

package com.hy.delete.singlethread;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.apache.log4j.Logger;

import com.hy.DBParam;

/**
 * 多表单线程删除
 * Single thread table deleter
 * @author 逆火
 *
 * 2019年11月17日 上午8:42:41
 */
public class BatchDeleter {
    private static Logger log = Logger.getLogger(BatchDeleter.class);

    // Commit size
    private static final int commitSize=10000;

    private String[] tablenames= {    "TestTB01",
            "TestTB02",
            "TestTB03",
            "TestTB04",
            "TestTB05",
            "TestTB06",
            "TestTB07",
            "TestTB08",
            "TestTB09",
            "TestTB10",
            "TestTB11",
            "TestTB12",
            "TestTB13",
            "TestTB14",
            "TestTB15",
            "TestTB16",
          };

    /**
     * 批量插入
     */
    public void batchDelete(String expiredDate) {
        Connection conn = null;
        Statement stmt = null;

        try{
            Class.forName(DBParam.Driver).newInstance();
            conn = DriverManager.getConnection(DBParam.DbUrl, DBParam.User, DBParam.Pswd);
            stmt = conn.createStatement();
            System.out.println("Begin to access "+DBParam.DbUrl+" as "+DBParam.User+"...");

            int index=1;
            for(String table:tablenames) {
                int total=delete(index,table,expiredDate,conn,stmt);
                log.info("#"+index+" "+total+" records deleted from table:'"+table+"'.");
                index++;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                stmt.close();
                conn.close();
            } catch (SQLException e) {
                log.error("Can't close stmt/conn because of " + e.getMessage());
            }
        }
    }

    /**
     * change seconds to DayHourMinuteSecond format
     * @param stratMs
     * @param endMs
     * @return
     */
    private static String sec2DHMS(long stratMs,long endMs) {
        String retval = null;
        long secondCount=(endMs-stratMs)/1000;

        long days = secondCount / (60 * 60 * 24);
        long hours = (secondCount % (60 * 60 * 24)) / (60 * 60);
        long minutes = (secondCount % (60 * 60)) / 60;
        long seconds = secondCount % 60;

        if (days > 0) {
            retval = days + "d" + hours + "h" + minutes + "m" + seconds + "s";
        } else if (hours > 0) {
            retval = hours + "h" + minutes + "m" + seconds + "s";
        } else if (minutes > 0) {
            retval = minutes + "m" + seconds + "s";
        } else {
            retval = seconds + "s";
        }

        return retval;
    }

    /**
     * 按日期删一张表的记录
     * @param tableIndex
     * @param table
     * @param expiredDate
     * @param conn
     * @param stmt
     * @throws SQLException
     */
    private int delete(int tableIndex,String table,String expiredDate,Connection conn,Statement stmt) throws SQLException {
        int totalDeleted=0;
        int expiredCount=0;

        do {
            String sql="delete from "+table+" WHERE CREATEDTIME < to_date('"+expiredDate+"','yyyy-MM-dd') and rownum<'"+commitSize+"' ";
            int deleted=stmt.executeUpdate(sql);
            //log.info("#"+tableIndex+" "+deleted+" records deleted from table:'"+table+"'.");
            totalDeleted+=deleted;

            expiredCount=queryExpiredCount(table,expiredDate,stmt);
        }while(expiredCount>0);

        return totalDeleted;
    }

    /**
     * 查询过期记录数量
     * @param table
     * @param expiredDate
     * @param conn
     * @param stmt
     * @return
     * @throws SQLException
     */
    private int queryExpiredCount(String table,String expiredDate,Statement stmt) throws SQLException {
        String sql="SELECT COUNT (*) as cnt FROM "+table+" WHERE CREATEDTIME < to_date('"+expiredDate+"','yyyy-MM-dd') and rownum<10 ";

        ResultSet rs = stmt.executeQuery(sql);

        while (rs.next()) {
            int count = rs.getInt("cnt");
            return count;
        }

        return 0;
    }

    public static void main(String[] args) {
        long startTime = System.currentTimeMillis();
        BatchDeleter bd=new BatchDeleter();
        bd.batchDelete("2019-07-17");
        long endTime = System.currentTimeMillis();
        log.info("Time elapsed:" + sec2DHMS(startTime,endTime) );
    }
}

输出：

Begin to access jdbc:oracle:thin:@127.0.0.1:1521:orcl as ufo...
2019-11-17 09:40:44,951 INFO[main]-#1 83077 records deleted from table:'TestTB01'.
2019-11-17 09:40:46,165 INFO[main]-#2 83077 records deleted from table:'TestTB02'.
2019-11-17 09:40:49,874 INFO[main]-#3 83077 records deleted from table:'TestTB03'.
2019-11-17 09:40:53,271 INFO[main]-#4 83077 records deleted from table:'TestTB04'.
2019-11-17 09:40:56,728 INFO[main]-#5 83077 records deleted from table:'TestTB05'.
2019-11-17 09:40:59,420 INFO[main]-#6 83077 records deleted from table:'TestTB06'.
2019-11-17 09:41:02,766 INFO[main]-#7 83077 records deleted from table:'TestTB07'.
2019-11-17 09:41:05,983 INFO[main]-#8 83077 records deleted from table:'TestTB08'.
2019-11-17 09:41:08,704 INFO[main]-#9 83077 records deleted from table:'TestTB09'.
2019-11-17 09:41:11,827 INFO[main]-#10 83077 records deleted from table:'TestTB10'.
2019-11-17 09:41:14,895 INFO[main]-#11 83077 records deleted from table:'TestTB11'.
2019-11-17 09:41:18,155 INFO[main]-#12 83077 records deleted from table:'TestTB12'.
2019-11-17 09:41:20,941 INFO[main]-#13 83077 records deleted from table:'TestTB13'.
2019-11-17 09:41:23,992 INFO[main]-#14 83077 records deleted from table:'TestTB14'.
2019-11-17 09:41:25,462 INFO[main]-#15 83077 records deleted from table:'TestTB15'.
2019-11-17 09:41:28,066 INFO[main]-#16 83077 records deleted from table:'TestTB16'.
2019-11-17 09:41:28,068 INFO[main]-Time elapsed:45s

多线程批量删除管理者类：

package com.hy.delete.multithread;

import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.Logger;

/**
 * 批量删表管理者
 * @author 逆火
 *
 * 2019年11月17日 上午9:54:46
 */
public class DeleteManager {
    private static Logger log = Logger.getLogger(DeleteManager.class);

    private String[] tablenames= {    "TestTB01",
            "TestTB02",
            "TestTB03",
            "TestTB04",
            "TestTB05",
            "TestTB06",
            "TestTB07",
            "TestTB08",
            "TestTB09",
            "TestTB10",
            "TestTB11",
            "TestTB12",
            "TestTB13",
            "TestTB14",
            "TestTB15",
            "TestTB16",
          };

    private long startTime;// Start time

    private List<DeleteJobInfo> jobInfos;// delete table informations

    /**
     * 批量插入
     */
    public void batchDelete(String expiredDate) {
        startTime=System.currentTimeMillis();
        jobInfos=new ArrayList<DeleteJobInfo>();

        int index=1;
        for(String table:tablenames) {
            DeleteThread dt=new DeleteThread(index,table,expiredDate,this);
            dt.start();
            index++;
        }
    }

    /**
     * Thread report manager "job done."
     * @param tbSN
     * @param tableName
     * @param timeElasped
     */
    public void reportFinished(String tbSN,String tableName,String timeElasped,String deleted) {
        jobInfos.add(new DeleteJobInfo(tbSN,tableName,timeElasped,deleted));

        if(jobInfos.size()==tablenames.length) {
            long endTime = System.currentTimeMillis();
            log.info(">>> Delete jobs finished.( time elapsed： " + sec2DHMS(startTime,endTime)+") <<<");

            log.info("------------ Details ------------");
            log.info("#,table,deleted,time elapsed");
            for(DeleteJobInfo jobInfo:jobInfos) {
                String raw="{0},{1},{2}";
                Object[] arr={jobInfo.tbSn,jobInfo.tableName,jobInfo.deleted,jobInfo.timeElapsed};
                String line=MessageFormat.format(raw, arr);
                log.info(line);
            }
            log.info("------------ Details ------------");

        }else {
            log.info(jobInfos.size()+" deleters completed their jobs.");
        }
    }

    /**
     * 成员内部类，用来做数据结构
     * 参考：https://blog.csdn.net/weixin_42762133/article/details/82890555
     * @author 逆火
     *
     * 2019年11月17日 上午9:22:04
     */
    protected static final class DeleteJobInfo{
        String tbSn;// 表序号
        String tableName;// 表名
        String timeElapsed;// 耗时
        String deleted;// count of deleted records

        public DeleteJobInfo(String tbSn,String tableName,String timeElapsed,String deleted) {
            this.tbSn=tbSn;
            this.tableName=tableName;
            this.timeElapsed=timeElapsed;
            this.deleted=deleted;
        }
    }

    /**
     * change seconds to DayHourMinuteSecond format
     * @param stratMs
     * @param endMs
     * @return
     */
    private static String sec2DHMS(long stratMs,long endMs) {
        String retval = null;
        long secondCount=(endMs-stratMs)/1000;

        long days = secondCount / (60 * 60 * 24);
        long hours = (secondCount % (60 * 60 * 24)) / (60 * 60);
        long minutes = (secondCount % (60 * 60)) / 60;
        long seconds = secondCount % 60;

        if (days > 0) {
            retval = days + "d" + hours + "h" + minutes + "m" + seconds + "s";
        } else if (hours > 0) {
            retval = hours + "h" + minutes + "m" + seconds + "s";
        } else if (minutes > 0) {
            retval = minutes + "m" + seconds + "s";
        } else {
            retval = seconds + "s";
        }

        return retval;
    }

    public static void main(String[] args) {
        DeleteManager dm=new DeleteManager();
        dm.batchDelete("2019-07-17");
    }
}

多线程删除删除者类：

package com.hy.delete.multithread;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.apache.log4j.Logger;

import com.hy.DBParam;

public class DeleteThread extends Thread {
    private static Logger log = Logger.getLogger(DeleteThread.class);

    // Commit size
    private static final int commitSize=10000;

    private int tableIndex;// table serial number
    private String table;// table will be deleted
    private String expiredDate;// expired date
    private DeleteManager menager; // reference to manager

    public DeleteThread(int tableIndex,String table,String expiredDate,DeleteManager menager) {
        this.tableIndex=tableIndex;
        this.table=table;
        this.expiredDate=expiredDate;
        this.menager=menager;
    }

    public void run() {
        Connection conn = null;
        Statement stmt = null;

        try{
            long startTime = System.currentTimeMillis();

            Class.forName(DBParam.Driver).newInstance();
            conn = DriverManager.getConnection(DBParam.DbUrl, DBParam.User, DBParam.Pswd);
            stmt = conn.createStatement();
            log.info("Begin to access "+DBParam.DbUrl+" as "+DBParam.User+"...");

            int total=delete(tableIndex,table,expiredDate,conn,stmt);
            log.info("#"+tableIndex+" "+total+" records deleted from table:'"+table+"'.");

            long endTime = System.currentTimeMillis();
            String timeElasped=sec2DHMS(startTime,endTime);
            menager.reportFinished(String.valueOf(tableIndex), table, timeElasped,String.valueOf(total));
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                stmt.close();
                conn.close();
            } catch (SQLException e) {
                log.error("Can't close stmt/conn because of " + e.getMessage());
            }
        }
    }

     /**
     * 按日期删一张表的记录
     * @param tableIndex
     * @param table
     * @param expiredDate
     * @param conn
     * @param stmt
     * @throws SQLException
     */
    private int delete(int tableIndex,String table,String expiredDate,Connection conn,Statement stmt) throws SQLException {
        int totalDeleted=0;
        int expiredCount=0;

        do {
            String sql="delete from "+table+" WHERE CREATEDTIME < to_date('"+expiredDate+"','yyyy-MM-dd') and rownum<'"+commitSize+"' ";
            int deleted=stmt.executeUpdate(sql);
            //log.info("#"+tableIndex+" "+deleted+" records deleted from table:'"+table+"'.");
            totalDeleted+=deleted;

            expiredCount=queryExpiredCount(table,expiredDate,stmt);
        }while(expiredCount>0);

        return totalDeleted;
    }

    /**
     * 查询过期记录数量
     * @param table
     * @param expiredDate
     * @param conn
     * @param stmt
     * @return
     * @throws SQLException
     */
    private int queryExpiredCount(String table,String expiredDate,Statement stmt) throws SQLException {
        String sql="SELECT COUNT (*) as cnt FROM "+table+" WHERE CREATEDTIME < to_date('"+expiredDate+"','yyyy-MM-dd') and rownum<10 ";

        ResultSet rs = stmt.executeQuery(sql);

        while (rs.next()) {
            int count = rs.getInt("cnt");
            return count;
        }

        return 0;
    }

    /**
     * change seconds to DayHourMinuteSecond format
     * @param stratMs
     * @param endMs
     * @return
     */
    private static String sec2DHMS(long stratMs,long endMs) {
        String retval = null;
        long secondCount=(endMs-stratMs)/1000;

        long days = secondCount / (60 * 60 * 24);
        long hours = (secondCount % (60 * 60 * 24)) / (60 * 60);
        long minutes = (secondCount % (60 * 60)) / 60;
        long seconds = secondCount % 60;

        if (days > 0) {
            retval = days + "d" + hours + "h" + minutes + "m" + seconds + "s";
        } else if (hours > 0) {
            retval = hours + "h" + minutes + "m" + seconds + "s";
        } else if (minutes > 0) {
            retval = minutes + "m" + seconds + "s";
        } else {
            retval = seconds + "s";
        }

        return retval;
    }
}

这个例子也证明了多线程相对于单线程的优势。

--END-- 2019年11月17日11:24:17