ASP.NET SQLServer2005 数据库备份与还原

  1 using System;

  2 using System.Data.SqlClient;

  3 using System.Data;

  4 using System.IO;

  5 

  6 namespace NET.Common

  7 {

  8     /// <summary>

  9     /// 数据库操作帮助类

 10     /// </summary>

 11     public class DatabaseHelper

 12     {

 13         private const string SQL_DATABASE_BACK = "BACKUP DATABASE {0} TO DISK = '{1}'"; //数据库备份语句

 14         private const string SQL_DATABASE_RESTORE = "RESTORE DATABASE {0} FROM DISK = '{1}' WITH REPLACE"; //数据库还原语句

 15         private const string SQL_SELECT_ALL_CONN = "SELECT spid FROM master..sysprocesses WHERE dbid=db_id('{0}')"; //获取指定数据库所有链接语句

 16 

 17         /// <summary>

 18         /// 实例数据库操作

 19         /// </summary>

 20         /// <param name="masterConnectionString">master数据库链接字符串</param>

 21         public DatabaseHelper(string masterConnectionString)

 22         {

 23             this.MasterConnectionString = masterConnectionString;

 24         }

 25 

 26         /// <summary>

 27         /// master数据库链接字符串

 28         /// </summary>

 29         private string MasterConnectionString { get; set; }

 30 

 31         /// <summary>

 32         /// SQLServer数据库备份

 33         /// </summary>

 34         /// <param name="connectionString">数据库连接字符串</param>

 35         /// <param name="backName">备份文件名称，不包含后缀名</param>

 36         /// <param name="path">备份文件存放的物理路径</param>

 37         public bool Back(string dbName, string backName, string path)

 38         {

 39             //判断存放备份文件的目录是否存在

 40             if (!Directory.Exists(path))

 41             {

 42                 //不存在，新建目录

 43                 Directory.CreateDirectory(path);

 44             }

 45 

 46             try

 47             {

 48                 using (SqlConnection conn = new SqlConnection(MasterConnectionString))

 49                 {

 50                     //设置存放备份文件的完整物理路径

 51                     string backPath = path + "\\" + backName + ".bak";

 52 

 53                     //设置数据库备份的T-SQL语句

 54                     string t_sql_back = string.Format(SQL_DATABASE_BACK, dbName, backPath);

 55 

 56                     using (SqlCommand cmd = new SqlCommand(t_sql_back, conn))

 57                     {

 58                         cmd.CommandType = CommandType.Text;

 59                         conn.Open();

 60 

 61                         //开始备份

 62                         cmd.ExecuteNonQuery();

 63 

 64                         return true;

 65                     }

 66                 }

 67             }

 68             catch

 69             {

 70                 return false;

 71             }

 72         }

 73 

 74         /// <summary>

 75         /// SQLServer数据库还原

 76         /// </summary>

 77         /// <param name="dbName">要进行还原的数据库名称</param>

 78         /// <param name="fullPath">备份文件的完整物理路径</param>

 79         public bool Restore(string dbName, string fullPath)

 80         {

 81             //判断还原使用的文件是否存在

 82             if (!File.Exists(fullPath))

 83             {

 84                 return false;

 85             }

 86 

 87             try

 88             {

 89                 using (SqlConnection conn = new SqlConnection(MasterConnectionString))

 90                 {

 91                     //设置数据库还原的T-SQL语句

 92                     string t_sql_restore = string.Format(SQL_DATABASE_RESTORE, dbName, fullPath);

 93 

 94                     //设置查询指定数据库的所有连接

 95                     string t_sql_select_all_conn = string.Format(SQL_SELECT_ALL_CONN, dbName);

 96 

 97                     string t_sql_kill;

 98 

 99                     conn.Open();

100 

101                     //获取指定数据库所有连接

102                     SqlCommand cmd = new SqlCommand(t_sql_select_all_conn, conn);

103                     SqlDataAdapter reSDA = new SqlDataAdapter(cmd);

104                     DataTable dtConn = new DataTable();

105                     reSDA.Fill(dtConn);

106 

107                     //逐一删除连接

108                     for (int i = 0; i < dtConn.Rows.Count; i++)

109                     {

110                         t_sql_kill = " kill  " + dtConn.Rows[i][0].ToString();

111                         cmd = new SqlCommand(t_sql_kill, conn);

112                         cmd.ExecuteNonQuery();

113                     }

114 

115                     //执行还原操作

116                     cmd = new SqlCommand(t_sql_restore, conn);

117                     cmd.ExecuteNonQuery();

118 

119                     //清空当前连接池，这个很主要，如果不清空还原后第一次访问会出现“在向服务器发送请求时发生传输级错误。 (provider: 共享内存提供程序, error: 0 - 管道的另一端上无任何进程。)”错误

120                     SqlConnection.ClearPool(conn);

121                     return true;

122                 }

123 

124             }

125             catch

126             {

127                 return false;

128             }

129         }

130     }

131 }