deleterecorddemo.java

java程序设计教程的源码

//【例12-13】  删除BLOB数据。
//程序清单12-13:  DeleteRecordDemo.java
package blob.document.mssqlserver;

import java.sql.*;
import db.connection.DatabaseConnection;

public class DeleteRecordDemo {
	private Connection con = null;

	private Statement smt = null;

	private PreparedStatement pstm = null;

	private ResultSet rset = null;

	public static void main(String[] args) {
		new DeleteRecordDemo();
	}

	public DeleteRecordDemo() {
		try {// 连接数据库
			con = new DatabaseConnection().getMsSqlServerConnection(
					"DBdocument", "sa", "ok");
			smt = con.createStatement();
		} catch (SQLException e) {
			e.getMessage();
		}
		// 删除指定文档号记录
		deleteRecoredByPid("2");
		// 显示输出
		showAllRecord();
		System.out.println("------------------");
		// 删除全部记录
		deleteAllRecored();
		// 显示输出
		showAllRecord();
		// 关闭连接
		closeAll(con, smt, pstm, rset);
	}

	public void deleteRecoredByPid(String docid) {
		try { // 删除记录
			pstm = con
					.prepareStatement("delete from tbldocuments where docid=?");
			pstm.setString(1, docid);
			if (pstm.executeUpdate() == 1) {
				System.out.println("删除数据表tbldocuments中文档号为" + docid + "的记录！");
			} else {
				System.out
						.println("数据表tbldocuments中没有待删除文档号为" + docid + "的记录！");
			}
		} catch (SQLException e) {
			System.out.println("SQLException:" + e.getMessage());
		}
	}

	public void deleteAllRecored() {
		try {
			String delete = "delete tbldocuments ";
			pstm = con.prepareStatement(delete);
			// 删除全部记录
			int rc = pstm.executeUpdate();
			System.out.println("成功:删除数据表tbldocuments中的全部" + rc + "条记录！");
		} catch (SQLException e) {
			System.out.println("SQLException:" + e.getMessage());
		}
	}

	public void showAllRecord() {
		try {// 查询数据库并把数据表的内容输出到屏幕上
			rset = smt.executeQuery("select * from tbldocuments");
			while (rset.next()) {
				System.out.println(rset.getString("docid") + "\t"
						+ rset.getString("docname") + "\t"
						+ rset.getString("docdescription"));
			}
		} catch (SQLException e) {
			System.out.println("SQLException:" + e.getMessage());
		}
	}

	public void closeAll(Connection con, Statement smt, PreparedStatement pstm,
			ResultSet rset) {
		try {
			con.close();
			smt.close();
			pstm.close();
			rset.close();
		} catch (SQLException e) {
			e.getMessage();
		}
	}
}