删除Postgresql数据库

Question

我正在尝试从asp.net (c#)中删除数据库。但它给了我一个错误:有一些联系。如果我删除所有的连接:

SELECT pg_terminate_backend (pg_stat_activity.pid) FROM pg_stat_activity 
WHERE pg_stat_activity.pid <> pg_backend_pid() and pg_stat_activity.datname = 'databsename';

它给了我另一个错误:连接丢失。

就像我执行上面的句子，它关闭了我所有的连接。

我使用npgsql作为连接器。

下面是我的代码:按钮内部的代码:

NpgsqlConnection _connPgComienzo = new NpgsqlConnection("my_connection_to_other_DDBB_in_the_same_server;");
    try
    {
        _connPgComienzo.Open();
        FileInfo file1 = new FileInfo(Server.MapPath("desconectar.sql"));
        string script_crear_bbdd = file1.OpenText().ReadToEnd();
        var m_createdb_cmd1 = new NpgsqlCommand(script_crear_bbdd, _connPgComienzo);
        m_createdb_cmd1.ExecuteNonQuery();
        _connPgComienzo.Close();
        _connPgComienzo.Open();
        FileInfo file2 = new FileInfo(Server.MapPath("drop_bbdd.sql"));
        string script_crear_bbdd2 = file2.OpenText().ReadToEnd();
        var m_createdb_cmd2 = new NpgsqlCommand(script_crear_bbdd2, _connPgComienzo);
        m_createdb_cmd2.ExecuteNonQuery();
        _connPgComienzo.Close();
    }
    catch (Exception ex)
    {
    }

desconectar.slq:

SELECT pg_terminate_backend (pg_stat_activity.pid) FROM pg_stat_activity 
WHERE pid <> pg_backend_pid() AND pg_stat_activity.datname = 'theDDBBIWantToDrop';

drop_bbdd.sql:

 DROP DATABASE theDDBBIWantToDrop;

Answer 1

*尝试使用psql终止您的postgreSQL database

• 为此，您必须使用c#创建batch file(*.bat)，该.bat文件必须包含以下脚本以终止您的数据库连接

psql -U postgres -d postgres -c SELECT pg_terminate_backend(pg_stat_activity.pid) FROM pg_stat_activity WHERE pg_stat_activity.piddatname = ' yourdb '

例如

Private Sub TerminateDBactivity()
    Dim strPG_dumpPath As String
    Dim strSub As String
    strPG_dumpPath = Application.StartupPath.ToString()
    strPG_dumpPath = strPG_dumpPath.Replace("", "\")
    Dim a As Integer = strPG_dumpPath.IndexOf(":\", 0)
    a = a + 2
    strSub = strPG_dumpPath.Substring(0, (a - 2))
    strPG_dumpPath = strPG_dumpPath.Substring(a, (strPG_dumpPath.Length - a))
    Dim sbSB1 As New StringBuilder(strPG_dumpPath)
    sbSB1 = sbSB1.Replace("\", vbCrLf & vbCrLf & "cd ")
    Dim sbSB2 As New StringBuilder("cd /D ")
    sbSB2 = sbSB2.Append(strSub)
    sbSB2 = sbSB2.Append(":")
    sbSB1 = sbSB2.Append(sbSB1)
    sbSB1 = sbSB1.Append(vbCrLf & vbCrLf & "cd PG" & vbCrLf & vbCrLf)
    Dim sw As New StreamWriter(Application.StartupPath.ToString() & "PGpgTerminate.bat")
    If sbSB1.Length <> 0 Then
        sbSB1 = sbSB1.Append("psql -U postgres  -d postgres -c ""SELECT pg_terminate_backend(pg_stat_activity.pid) FROM pg_stat_activity WHERE pg_stat_activity.datname = '" & gStrDBName & "';")
        sw.WriteLine(sbSB1)
        sw.Dispose()
        sw.Close()
        Dim processDB As New ProcessStartInfo
        processDB.FileName = Application.StartupPath.ToString() & "PGpgTerminate.bat"
        processDB.WindowStyle = ProcessWindowStyle.Hidden
        Process.Start(processDB).WaitForExit()
        Cursor.Current = Cursors.Default
    End If
End Sub

• 此代码将在此路径下创建pgTerminate.bat文件D:AppsRSTAR PGSQL DOTCONNECTbinDebugPG

• pgTerminate.bat look like

  cd/D D:Apps

cd RSTAR PGSQL DOTCONNECT
cd bin
cd Debug
cd PG
psql -U postgres  -d postgres -c SELECT pg_terminate_backend(pg_stat_activity.pid) FROM pg_stat_activity WHERE pg_stat_activity.datname = 'mydb';

注意:在尝试代码之前，你应该手动创建终止bat文件并测试它是否工作