2018-03-08 JDBC批处理

预处理语句对象 PreparedStatement

    String sql = "delete from ajia_user where id=?";

    PreparedStatement pstmt

    = conn.prepareStatement(sql);

        如果删除10条数据，与数据库交互10次

    for(int id:ids){

    pstmt.setInt(1,id);

    //将操作添加到语句列表中

    pstmt.addBatch();

    //pstmt.executeUpdate();

    //一次性缓存一组数据

    在语句对象中，维护了一个语句列表

    }

    //一次性执行一组操作

    pstmt.executeBatch();   

    addBatch(),填充语句列表

    executeBatch(),执行语句列表

    clearBatch(),清除语句列表

public class JdbcDemo1 {

    public static void main(String[] args) {

        int[] ids = {70,71};

        String sql = "DELETE FROM ajia_user WHERE id=?";

        Connection conn = null;

        boolean autoCommit = false;

        try { conn = JdbcUtil.getConn();

        autoCommit = conn.getAutoCommit();

        conn.setAutoCommit(false);

        PreparedStatement pstmt = conn.prepareStatement(sql);

        for(int id:ids){

        pstmt.setInt(1, id);

        //添加到语句列表中

        pstmt.addBatch();

        }

        //执行语句列表 pstmt.executeBatch();

        //默认JDBC自动给数据库发送commit指令 conn.commit();

        //关闭语句对象

        pstmt.close();

        } catch (SQLException e) {

        try {

        conn.rollback();

        } catch (SQLException e1) {

        e1.printStackTrace();

        } e.printStackTrace();

        }finally{ try {

        conn.setAutoCommit(autoCommit);

        } catch (SQLException e) {

        e.printStackTrace();

        } JdbcUtil.close(conn); } } }