sqlcommand.endexecutenonqueryを使用する場合のSQL構文エラー

Question

バックグラウンドワーカーで非同期に、2つのSQLステートメント（MSSQL 2005）を実行しようとしています。ただし、最初のSQLCommandでEndexeCutenonQueryメソッドを呼び出すと、 'SQL構文エラーがエラー近くで登場します。

これが私のコードです：

try
{
    SqlCommand sqlCmd = uow.DataLayer.CreateCommand() as SqlCommand;
    sqlCmd.CommandText = "DELETE FROM dbo.EligibilityRecordKeyValue WHERE EligibilityRecord IN " +
    "(SELECT EligibilityRecord FROM dbo.EligibilityRecord WHERE Organization = '" + map.Organization.Oid + "')";
    IAsyncResult result = sqlCmd.BeginExecuteNonQuery();
    while (!result.IsCompleted)
    {
        worker.ReportProgress(0, "Deleting existing record keys");
        System.Threading.Thread.Sleep(200);
    }
    count = sqlCmd.EndExecuteNonQuery(result);
}
catch (SqlException ex)
{
}
catch (InvalidOperationException ex)
{
}
finally
{
    worker.ReportProgress(2, String.Format("Existing {0} records keys deleted.", count));
}

try
{
    SqlCommand sqlCmd = uow.DataLayer.CreateCommand() as SqlCommand;
    sqlCmd.CommandText = "DELETE FROM dbo.EligibilityRecord WHERE Organization = '" +      map.Organization.Oid + "'";
    IAsyncResult result = sqlCmd.BeginExecuteNonQuery();
    while (!result.IsCompleted)
    {
        worker.ReportProgress(0, "Deleting existing records");
        System.Threading.Thread.Sleep(200);
    }
    count = sqlCmd.EndExecuteNonQuery(result);
}
catch (SqlException ex)
{
}
catch (InvalidOperationException ex)
{
}
finally
{
    worker.ReportProgress(5, String.Format("Existing {0} records deleted.", count));
}

最初に失敗します count = sqlCmd.EndExecuteNonQuery(result);

Answer 1

OK、両方のSQLコマンドに遅延を追加すると、問題が解決されたようです。

sqlCmd.CommandText = String.Format("WAITFOR DELAY '00:00:05'; DELETE FROM dbo.EligibilityRecordKeyValue WHERE EligibilityRecord IN " + 
                    "(SELECT EligibilityRecord FROM dbo.EligibilityRecord WHERE Organization = '{0}')", map.Organization.Oid);

sqlCmd.CommandText = String.Format("WAITFOR DELAY '00:00:05'; DELETE FROM dbo.EligibilityRecord WHERE Organization = '{0}'", map.Organization.Oid);

なぜこれが起こるのか知っていますか？