想往某個表中插入幾百萬條數據作下測試,java
原先的想法,直接寫個循環10W次隨便插入點數據試試吧,好吧,我真的很天真....mysql
DROP PROCEDURE IF EXISTS proc_initData;--若是存在此存儲過程則刪掉 DELIMITER $ CREATE PROCEDURE proc_initData() BEGIN DECLARE i INT DEFAULT 1; WHILE i<=100000 DO INSERT INTO text VALUES(i,CONCAT('姓名',i),'XXXXXXXXX'); SET i = i+1; END WHILE; END $ CALL proc_initData();
執行CALL proc_initData()後,原本想一想,再慢10W條數據頂多30分鐘能搞定吧,結果我打了2把LOL後,回頭一看,還在執行,此時內心是完全懵逼的....待我打完第三把結束後,終於執行完了,這種方法如果讓我等上幾百萬條數據,是否是早上去上班,下午下班回來還沒結束呢?10W條數據,有圖有真相sql
後面查了一下,使用JDBC批量操做往數據庫插入100W+的數據貌似也挺快的,數據庫
先來講說JDBC往數據庫中普通插入方式,簡單的代碼大體以下,循環了1000條,中間加點隨機的數值,畢竟本身要拿數據測試,數據全都同樣也很差區分dom
1 private String url = "jdbc:mysql://localhost:3306/test01"; 2 private String user = "root"; 3 private String password = "123456"; 4 @Test 5 public void Test(){ 6 Connection conn = null; 7 PreparedStatement pstm =null; 8 ResultSet rt = null; 9 try { 10 Class.forName("com.mysql.jdbc.Driver"); 11 conn = DriverManager.getConnection(url, user, password); 12 String sql = "INSERT INTO userinfo(uid,uname,uphone,uaddress) VALUES(?,CONCAT('姓名',?),?,?)"; 13 pstm = conn.prepareStatement(sql); 14 Long startTime = System.currentTimeMillis(); 15 Random rand = new Random(); 16 int a,b,c,d; 17 for (int i = 1; i <= 1000; i++) { 18 pstm.setInt(1, i); 19 pstm.setInt(2, i); 20 a = rand.nextInt(10); 21 b = rand.nextInt(10); 22 c = rand.nextInt(10); 23 d = rand.nextInt(10); 24 pstm.setString(3, "188"+a+"88"+b+c+"66"+d); 25 pstm.setString(4, "xxxxxxxxxx_"+"188"+a+"88"+b+c+"66"+d);27 pstm.executeUpdate(); 28 } 29 Long endTime = System.currentTimeMillis(); 30 System.out.println("OK,用時:" + (endTime - startTime)); 31 } catch (Exception e) { 32 e.printStackTrace(); 33 throw new RuntimeException(e); 34 }finally{ 35 if(pstm!=null){ 36 try { 37 pstm.close(); 38 } catch (SQLException e) { 39 e.printStackTrace(); 40 throw new RuntimeException(e); 41 } 42 } 43 if(conn!=null){ 44 try { 45 conn.close(); 46 } catch (SQLException e) { 47 e.printStackTrace(); 48 throw new RuntimeException(e); 49 } 50 } 51 } 52 }
輸出結果:OK,用時:738199,單位毫秒,也就是說這種方式與直接數據庫中循環是差很少的。測試
在討論批量處理以前,先說說遇到的坑,首先,JDBC鏈接的url中要加rewriteBatchedStatements參數設爲true是批量操做的前提,其次就是檢查mysql驅動包時候是5.1.13以上版本(低於該版本不支持),因網上隨便下載了5.1.7版本的,而後執行批量操做(100W條插入),結果由於驅動器版本過低緣故並不支持,致使中止掉java程序後,mysql還在不斷的往數據庫中插入數據,最後不得不中止掉數據庫服務才停下來...ui
那麼低版本的驅動包是否對100W+數據插入就無力了呢?實際還有另一種方式,效率相比來講仍是能夠接受的。url
先將命令的提交方式設爲false,即手動提交conn.setAutoCommit(false);最後在全部命令執行完以後再提交事務conn.commit();spa
1 private String url = "jdbc:mysql://localhost:3306/test01"; 2 private String user = "root"; 3 private String password = "123456"; 4 @Test 5 public void Test(){ 6 Connection conn = null; 7 PreparedStatement pstm =null; 8 ResultSet rt = null; 9 try { 10 Class.forName("com.mysql.jdbc.Driver"); 11 conn = DriverManager.getConnection(url, user, password); 12 String sql = "INSERT INTO userinfo(uid,uname,uphone,uaddress) VALUES(?,CONCAT('姓名',?),?,?)"; 13 pstm = conn.prepareStatement(sql); 14 conn.setAutoCommit(false); 15 Long startTime = System.currentTimeMillis(); 16 Random rand = new Random(); 17 int a,b,c,d; 18 for (int i = 1; i <= 100000; i++) { 19 pstm.setInt(1, i); 20 pstm.setInt(2, i); 21 a = rand.nextInt(10); 22 b = rand.nextInt(10); 23 c = rand.nextInt(10); 24 d = rand.nextInt(10); 25 pstm.setString(3, "188"+a+"88"+b+c+"66"+d); 26 pstm.setString(4, "xxxxxxxxxx_"+"188"+a+"88"+b+c+"66"+d); 27 pstm.executeUpdate(); 28 } 29 conn.commit(); 30 Long endTime = System.currentTimeMillis(); 31 System.out.println("OK,用時:" + (endTime - startTime)); 32 } catch (Exception e) { 33 e.printStackTrace(); 34 throw new RuntimeException(e); 35 }finally{ 36 if(pstm!=null){ 37 try { 38 pstm.close(); 39 } catch (SQLException e) { 40 e.printStackTrace(); 41 throw new RuntimeException(e); 42 } 43 } 44 if(conn!=null){ 45 try { 46 conn.close(); 47 } catch (SQLException e) { 48 e.printStackTrace(); 49 throw new RuntimeException(e); 50 } 51 } 52 } 53 }
以上代碼插入10W條數據,輸出結果:OK,用時:18086,也就十八秒左右的時間,理論上100W也就是3分鐘這樣,勉強還能夠接受。code
接下來就是批量處理了,注意,必定要5.1.13以上版本的驅動包。
1 private String url = "jdbc:mysql://localhost:3306/test01?rewriteBatchedStatements=true"; 2 private String user = "root"; 3 private String password = "123456"; 4 @Test 5 public void Test(){ 6 Connection conn = null; 7 PreparedStatement pstm =null; 8 ResultSet rt = null; 9 try { 10 Class.forName("com.mysql.jdbc.Driver"); 11 conn = DriverManager.getConnection(url, user, password); 12 String sql = "INSERT INTO userinfo(uid,uname,uphone,uaddress) VALUES(?,CONCAT('姓名',?),?,?)"; 13 pstm = conn.prepareStatement(sql); 14 Long startTime = System.currentTimeMillis(); 15 Random rand = new Random(); 16 int a,b,c,d; 17 for (int i = 1; i <= 100000; i++) { 18 pstm.setInt(1, i); 19 pstm.setInt(2, i); 20 a = rand.nextInt(10); 21 b = rand.nextInt(10); 22 c = rand.nextInt(10); 23 d = rand.nextInt(10); 24 pstm.setString(3, "188"+a+"88"+b+c+"66"+d); 25 pstm.setString(4, "xxxxxxxxxx_"+"188"+a+"88"+b+c+"66"+d); 26 pstm.addBatch(); 27 } 28 pstm.executeBatch(); 29 Long endTime = System.currentTimeMillis(); 30 System.out.println("OK,用時:" + (endTime - startTime)); 31 } catch (Exception e) { 32 e.printStackTrace(); 33 throw new RuntimeException(e); 34 }finally{ 35 if(pstm!=null){ 36 try { 37 pstm.close(); 38 } catch (SQLException e) { 39 e.printStackTrace(); 40 throw new RuntimeException(e); 41 } 42 } 43 if(conn!=null){ 44 try { 45 conn.close(); 46 } catch (SQLException e) { 47 e.printStackTrace(); 48 throw new RuntimeException(e); 49 } 50 } 51 } 52 }
10W輸出結果:OK,用時:3386,才3秒鐘.
而後我就想,要是批量操做+事務提交呢?會不會有神器的效果?
1 private String url = "jdbc:mysql://localhost:3306/test01?rewriteBatchedStatements=true"; 2 private String user = "root"; 3 private String password = "123456"; 4 @Test 5 public void Test(){ 6 Connection conn = null; 7 PreparedStatement pstm =null; 8 ResultSet rt = null; 9 try { 10 Class.forName("com.mysql.jdbc.Driver"); 11 conn = DriverManager.getConnection(url, user, password); 12 String sql = "INSERT INTO userinfo(uid,uname,uphone,uaddress) VALUES(?,CONCAT('姓名',?),?,?)"; 13 pstm = conn.prepareStatement(sql); 14 conn.setAutoCommit(false); 15 Long startTime = System.currentTimeMillis(); 16 Random rand = new Random(); 17 int a,b,c,d; 18 for (int i = 1; i <= 100000; i++) { 19 pstm.setInt(1, i); 20 pstm.setInt(2, i); 21 a = rand.nextInt(10); 22 b = rand.nextInt(10); 23 c = rand.nextInt(10); 24 d = rand.nextInt(10); 25 pstm.setString(3, "188"+a+"88"+b+c+"66"+d); 26 pstm.setString(4, "xxxxxxxxxx_"+"188"+a+"88"+b+c+"66"+d); 27 pstm.addBatch(); 28 } 29 pstm.executeBatch(); 30 conn.commit(); 31 Long endTime = System.currentTimeMillis(); 32 System.out.println("OK,用時:" + (endTime - startTime)); 33 } catch (Exception e) { 34 e.printStackTrace(); 35 throw new RuntimeException(e); 36 }finally{ 37 if(pstm!=null){ 38 try { 39 pstm.close(); 40 } catch (SQLException e) { 41 e.printStackTrace(); 42 throw new RuntimeException(e); 43 } 44 } 45 if(conn!=null){ 46 try { 47 conn.close(); 48 } catch (SQLException e) { 49 e.printStackTrace(); 50 throw new RuntimeException(e); 51 } 52 } 53 } 54 }
如下是100W數據輸出對比:(5.1.17版本MySql驅動包下測試,交替兩種方式下的數據測試結果對比)
批量操做(10W) | 批量操做+事務提交(10W) | 批量操做(100W) | 批量錯做+事務提交(100W) |
OK,用時:3901 |
OK,用時:3343 |
OK,用時:44242 |
OK,用時:39798 |
OK,用時:4142 |
OK,用時:2949 |
OK,用時:44248 |
OK,用時:39959 |
OK,用時:3664 |
OK,用時:2689 |
OK,用時:44389 |
OK,用時:39367 |
可見有必定的效率提高,可是並非太明顯,固然由於數據差不算太大,也有可能存在偶然因數,畢竟每項只測3次。
網上還有人說使用預編譯+批量操做的方式可以提升效率更明顯,可是本人親測,效率不高反降,可能跟測試的數據有關吧。
預編譯的寫法,只需在JDBC的鏈接url中將寫入useServerPrepStmts=true便可,
如:
private String url = "jdbc:mysql://localhost:3306/test01?useServerPrepStmts=true&rewriteBatchedStatements=true"
好了,先到這裏...