Java Tutorial/Database/Batch Update

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Версия от 05:05, 1 июня 2010; Admin (обсуждение | вклад) (1 версия)
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Add batch SQL command into Statement

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement st = conn .createStatement();
    
    
    st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
    st.addBatch("DELETE FROM survey");
    st.addBatch("INSERT INTO survey(id, name) "+
                  "VALUES(444, "ginger")");
    // we intentionally pass a table name (animals_tableZZ)
    // that does not exist
    st.addBatch("INSERT INTO survey(id, name) "+
                  "VALUES(555, "lola")");
    st.addBatch("INSERT INTO survey(id, name) "+
                  "VALUES(666, "freddy")");
    // Execute the batch
    int[] updateCounts = st.executeBatch();
    
    checkUpdateCounts(updateCounts);
    // since there were no errors, commit
    conn.rumit();
    
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);
    
    rs.close();
    st.close();
    conn.close();
  }
  public static void checkUpdateCounts(int[] updateCounts) {
    for (int i=0; i<updateCounts.length; i++) {
        if (updateCounts[i] >= 0) {
            System.out.println("OK; updateCount="+updateCounts[i]);
        }
        else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
            System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
        }
        else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
            System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
        }
    }
}  
  
  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");
    }
    System.out.println();
    System.out.println("----------------------");
    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }
  }
  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
}



OK; updateCount=0
OK; updateCount=1
OK; updateCount=1
OK; updateCount=1
ID   NAME   
----------------------
444   ginger   
555   lola   
666   freddy


Check Batch Update count

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement st = conn .createStatement();
    
    
    st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
    
    String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
    
    PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
    pstmt.setString(1, "1");
    pstmt.setString(2, "name1");
    pstmt.addBatch();
    
    pstmt.setString(1, "2");
    pstmt.setString(2, "name2");
    pstmt.addBatch();
    
    // execute the batch
    int[] updateCounts = pstmt.executeBatch();
    checkUpdateCounts(updateCounts);
    // since there were no errors, commit
    conn.rumit();
    
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);
    
    rs.close();
    st.close();
    conn.close();
  }
  public static void checkUpdateCounts(int[] updateCounts) {
    for (int i=0; i<updateCounts.length; i++) {
        if (updateCounts[i] >= 0) {
            System.out.println("OK; updateCount="+updateCounts[i]);
        }
        else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
            System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
        }
        else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
            System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
        }
    }
}  
  
  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");
    }
    System.out.println();
    System.out.println("----------------------");
    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }
  }
  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
}



OK; updateCount=1
OK; updateCount=1
ID   NAME   
----------------------
1   name1   
2   name2


Check BatchUpdateException

import java.sql.BatchUpdateException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement st = conn.createStatement();
    st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
    String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
    PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
    pstmt.setString(1, "1");
    pstmt.setString(2, "name1");
    pstmt.addBatch();
    pstmt.setString(1, "2");
    pstmt.setString(2, "name2");
    pstmt.addBatch();
    try {
      // execute the batch
      int[] updateCounts = pstmt.executeBatch();
    } catch (BatchUpdateException e) {
      int[] updateCounts = e.getUpdateCounts();
      checkUpdateCounts(updateCounts);
      try {
        conn.rollback();
      } catch (Exception e2) {
        e.printStackTrace();
        System.exit(1);
      }
    }
    // since there were no errors, commit
    conn.rumit();
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);
    rs.close();
    st.close();
    conn.close();
  }
  public static void checkUpdateCounts(int[] updateCounts) {
    for (int i = 0; i < updateCounts.length; i++) {
      if (updateCounts[i] >= 0) {
        System.out.println("OK; updateCount=" + updateCounts[i]);
      } else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
        System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
      } else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
        System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
      }
    }
  }
  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");
    }
    System.out.println();
    System.out.println("----------------------");
    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }
  }
  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
}



ID   NAME   
----------------------
1   name1   
2   name2


Determining If a Database Supports Scrollable Result Sets

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
public class Main {
  public static void main(String[] argv) throws Exception {
    String driverName = "com.jnetdirect.jsql.JSQLDriver";
    Class.forName(driverName);
    String serverName = "127.0.0.1";
    String portNumber = "1433";
    String mydatabase = serverName + ":" + portNumber;
    String url = "jdbc:JSQLConnect://" + mydatabase;
    String username = "username";
    String password = "password";
    Connection connection = DriverManager.getConnection(url, username, password);
    DatabaseMetaData dmd = connection.getMetaData();
    if (dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_INSENSITIVE)) {
        System.out.println("Insensitive scrollable result sets are supported");
    }
    if (dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_SENSITIVE)) {
        System.out.println("Sensitive scrollable result sets are supported"); 
    }
    if (!dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_INSENSITIVE)
        && !dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_SENSITIVE)) {
        System.out.println("Updatable result sets are not supported");
    }
  }
}





Use Batch Multiple Updates with PreparedStatement

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement st = conn .createStatement();
    
    
    st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
    
    String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
    
    PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
    pstmt.setString(1, "1");
    pstmt.setString(2, "name1");
    pstmt.addBatch();
    
    pstmt.setString(1, "2");
    pstmt.setString(2, "name2");
    pstmt.addBatch();
    
    // execute the batch
    int[] updateCounts = pstmt.executeBatch();
    checkUpdateCounts(updateCounts);
    // since there were no errors, commit
    conn.rumit();
    
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);
    
    rs.close();
    st.close();
    conn.close();
  }
  public static void checkUpdateCounts(int[] updateCounts) {
    for (int i=0; i<updateCounts.length; i++) {
        if (updateCounts[i] >= 0) {
            System.out.println("OK; updateCount="+updateCounts[i]);
        }
        else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
            System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
        }
        else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
            System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
        }
    }
}  
  
  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");
    }
    System.out.println();
    System.out.println("----------------------");
    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }
  }
  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
}



OK; updateCount=1
OK; updateCount=1
ID   NAME   
----------------------
1   name1   
2   name2


Using a Loop to Set Values

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] args) throws Exception {
    Connection conn = getConnection();
    conn.setAutoCommit(false);
    Statement st = conn .createStatement();
    
    
    st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
    
    String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
    
    PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
    for(int i=0;i<10;i++){
      pstmt.setInt(1, i);
      pstmt.setString(2, "name"+i);
      pstmt.executeUpdate();
    }

    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    outputResultSet(rs);
    
    rs.close();
    st.close();
    conn.close();
  }
  private static void outputResultSet(ResultSet rs) throws Exception {
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    for (int i = 1; i < numberOfColumns + 1; i++) {
      String columnName = rsMetaData.getColumnName(i);
      System.out.print(columnName + "   ");
    }
    System.out.println();
    System.out.println("----------------------");
    while (rs.next()) {
      for (int i = 1; i < numberOfColumns + 1; i++) {
        System.out.print(rs.getString(i) + "   ");
      }
      System.out.println();
    }
  }
  private static Connection getConnection() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    String url = "jdbc:hsqldb:mem:data/tutorial";
    return DriverManager.getConnection(url, "sa", "");
  }
}



ID   NAME   
----------------------
0   name0   
1   name1   
2   name2   
3   name3   
4   name4   
5   name5   
6   name6   
7   name7   
8   name8   
9   name9
Источник — «http://jexp.ru/index.php?title=Java_Tutorial/Database/Batch_Update&oldid=4772»