PowerShell正在尝试编写SQL工厂代码。。。

我正在编写一个需要多次sql连接的脚本。我需要平行学习来加快速度。这就是为什么我希望有一种SQL工厂，它会返回一个连接句柄。但不知为什么我的代码不起作用。我做错了什么

$m = New-Module -Name sql_factory -AsCustomObject -ScriptBlock {
    Function new_session {
        $db_host = 'my.sqlhost.tld';
        $db_user = 'user';
        $db_pass = 'pass'; 
        $db_name = 'db';
        $table_name = $env:COMPUTERNAME;

        $conn = New-Object system.data.sqlclient.sqlconnection;
        $conn.ConnectionString = "Server=${db_host};Database=${db_name};User ID=${db_user};Password=${db_pass};";

        $cmd = New-Object System.Data.SqlClient.SqlCommand; 
        $cmd.connection = $conn; 

        return $cmd, $conn; 
    }
}

$test = {
    $cmd, $conn = $m.new_session(); 

    $conn.Open();
    $cmd.CommandText = "INSERT INTO tableXXX (date, time, action, protocol, src_ip, dst_ip, src_port, dst_port, size, tcp_flags, tcpsyn, tcpack, tcpwin, icmptype, icmpcode, info, path) VALUES ('xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx')";
    $cmd.ExecuteNonQuery();
    $conn.Close();     
}

start-job -ScriptBlock $test | Out-Null
get-job | receive-job -AutoRemoveJob -Wait 

这是我收到的错误消息

You cannot call a method on a null-valued expression.
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull
    + PSComputerName        : localhost

You cannot call a method on a null-valued expression.
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull
    + PSComputerName        : localhost

Property 'CommandText' cannot be found on this object; make sure it exists and is settable.
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : PropertyNotFound
    + PSComputerName        : localhost

You cannot call a method on a null-valued expression.
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull
    + PSComputerName        : localhost

You cannot call a method on a null-valued expression.
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull
    + PSComputerName        : localhost

---

脚本块对您创建的模块一无所知。开始作业时，需要将其作为参数传递：

$test = {
  param($db_factory)

  $cmd, $conn = $db_factory.new_session()

  ...
}

Start-Job -ScriptBlock $test -ArgumentList $m | Out-Null
...

但是，由于您正在为每个作业创建新连接，因此您也可以将建立数据库连接的代码放在脚本块中：

$test = {
  param($db_host, $db_user, $db_pass, $db_name)

  $table_name = $env:COMPUTERNAME
  $cs = "Server=$db_host;Database=$db_name;User ID=$db_user;Password=$db_pass;"

  $conn = New-Object system.data.sqlclient.sqlconnection
  $conn.ConnectionString = $cs

  $cmd = New-Object System.Data.SqlClient.SqlCommand
  $cmd.connection = $conn

  $conn.Open()
  ...
}

Start-Job -ScriptBlock $test -ArgumentList 'my.sqlhost.tld','user','pass','db' |
  Out-Null
...

---

您还可以使用SQL Server管理对象（SMO）

---

谢谢你的回复。我不想将用于建立的代码放在“开始作业-脚本块”中，因为这会非常重复。我有几个insert是由start job启动的，它们并行运行，但我还有几个其他连接，用于设置数据库和表属性……您的代码的重复性并没有减少。只是有点复杂。

$m = {
 param($instanceName, $login, $pass, $dbName)
 #import SQL Server module
 Import-Module SQLPS -DisableNameChecking 

 #Create server connection
 $srvConn = New-Object Microsoft.SqlServer.Management.Common.ServerConnection
 $srvConn.ServerInstance = $instanceName
 $srvConn.LoginSecure = $false
 $srvConn.Login = $login
 $srvConn.Password = $pass

 #Initiate the object and set the database
 $srv = New-Object Microsoft.SqlServer.Management.SMO.Server($srvConn)
 $db = $srv.Databases[$dbName]
 #Execute T-SQL
 $db.ExecuteNonQuery("INSERT INTO tableXXX (date, time, action, protocol, src_ip, dst_ip, src_port, dst_port, size, tcp_flags, tcpsyn, tcpack, tcpwin, icmptype, icmpcode, info, path) VALUES ('xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx','xxx')")
}

start-job -ScriptBlock $m -ArgumentList 'my.sqlhost.tld','user','pass','db' | Out-Null
get-job | receive-job -AutoRemoveJob -Wait