C# 使用多线程SMO到Azure SQL

我有一个多线程服务，它使用SMO读取表名和列名，还可以更改数据库。我们目前正在研究Azure，并继续尝试那里的代码。它与SQL Server合作已经很长时间了。 在Azure SQL中，当只使用一个线程时，一切正常。当第二个线程在第一个线程仍在执行时开始读取时，将引发异常：

   System.InvalidOperationException: There is already an open DataReader associated with this Command which must be closed first.
   at System.Data.SqlClient.SqlInternalConnectionTds.ValidateConnectionForExecute(SqlCommand command)
   at System.Data.SqlClient.SqlCommand.ValidateCommand(String method, Boolean async)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader()
   at Microsoft.SqlServer.Management.Common.ConnectionManager.ExecuteTSql(ExecuteTSqlAction action, Object execObject, DataSet fillDataSet, Boolean catchException)
   at Microsoft.SqlServer.Management.Common.ServerConnection.GetExecuteReader(SqlCommand command)
   at Microsoft.SqlServer.Management.Smo.ExecuteSql.GetDataReader(String query, SqlCommand& command)
   at Microsoft.SqlServer.Management.Smo.DataProvider.SetConnectionAndQuery(ExecuteSql execSql, String query)
   at Microsoft.SqlServer.Management.Smo.ExecuteSql.GetDataProvider(StringCollection query, Object con, StatementBuilder sb, RetriveMode rm)
   at Microsoft.SqlServer.Management.Smo.SqlObjectBase.FillData(ResultType resultType, StringCollection sql, Object connectionInfo, StatementBuilder sb)
   at Microsoft.SqlServer.Management.Smo.SqlObjectBase.FillDataWithUseFailure(SqlEnumResult sqlresult, ResultType resultType)
   at Microsoft.SqlServer.Management.Smo.SqlObjectBase.BuildResult(EnumResult result)
   at Microsoft.SqlServer.Management.Sdk.Sfc.Environment.GetData()
   at Microsoft.SqlServer.Management.Sdk.Sfc.Environment.GetData(Request req, Object ci)
   at Microsoft.SqlServer.Management.Sdk.Sfc.Enumerator.GetData(Object connectionInfo, Request request)
   at Microsoft.SqlServer.Management.Smo.ExecutionManager.GetEnumeratorDataReader(Request req)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.GetInitDataReader(String[] fields, OrderBy[] orderby)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.ImplInitialize(String[] fields, OrderBy[] orderby)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.Initialize(Boolean allProperties)
   at Microsoft.SqlServer.Management.Smo.SmoCollectionBase.InitializeChildObject(ObjectKeyBase key)
   at Microsoft.SqlServer.Management.Smo.SmoCollectionBase.GetObjectByKey(ObjectKeyBase key)
   at Microsoft.SqlServer.Management.Smo.TableCollection.get_Item(String name)

激烈的谷歌搜索并没有产生任何可行的结果，若你们不在线程之间共享任何东西，那个么使用SMO应该没问题。我已经更新了微软新的官方SMO 2017 nuget软件包，但没有任何帮助。第一个线程完成后，第二个线程运行良好，所以只有一个线程可以读取数据库。 我们将不胜感激

我用来读取数据库的代码如下：

  private Database GetDataBase()
    {
        //do not have to get this from DB every time on same thread.
        if (_db != null) return _db;
        //GetConnection just returns new SqlConnection
        using (var conn = _executor.GetConnection() as SqlConnection)
        {
            conn.Open();
            var sConn = new ServerConnection(conn);
            var server = new Server(sConn);
            _db = server.Databases[sConn.DatabaseName];
            _db.DefaultSchema = "dbo";

            //Problem with Azure:
            //Enumerate these to ensure immediate crash, when 2nd thread kicks in
            //and 1st thread is still executing.
            //Works fine with SQL Server
            foreach (Table t in _db.Tables)
            {
                foreach (Column c in t.Columns)
                {

                }
            }
        }
        return _db;
    }

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Azure SQL中似乎不支持它。我假设Microsoft只在Azure SQL上实现了部分SMO。（如果我错了，请纠正我）。我重构了代码的SMO部分ouf，所以谁知道这是否仍然是一个问题。Azure SQL中似乎不支持它。我假设微软只在Azure SQL上实现了一部分SMO。（如果我错了，请纠正我）。我重构了代码的SMO部分ouf，所以谁知道，这是否仍然是一个问题。