根据tin bug修复data history与process log导出数据时间不一致问题

FrameworkLocal/Common/DataCollection/DataCollectionManager.cs

@@ -268,6 +268,7 @@ namespace Aitex.Core.RT.DataCollection
                     }
                     //insert data into database
                     StringBuilder sb = new StringBuilder(10000);
+                    string timeStr = string.Empty;
                     while (_bAlive)
                     {
                         //Thread.Sleep(990);
@@ -275,11 +276,12 @@ namespace Aitex.Core.RT.DataCollection
                         //if alert to another day, create a new table 
                         if (DateTime.Now.Date != dtToday)
                             break;
+                        timeStr = DateTime.Now.Ticks.ToString();
                         foreach (var module in _modules)
                         {
-                            sb.Remove(0, sb.Length);
+                            sb.Clear();
                             sb.Append("Values(");
-                            sb.Append(DateTime.Now.Ticks.ToString());
+                            sb.Append(timeStr);
                             foreach (var dataName in moduleDataItem[module].Keys)
                             {
                                 sb.Append(",");