ArcEngine,C#数据删除几种方法以及性能比较

时间:2022-01-10 19:26:39

一、  几种删除方法代码
1.  查询结果中删除
  private void Delete1(IFeatureClass PFeatureclass)
        {
            IQueryFilter pQueryFilter = new QueryFilterClass();
            pQueryFilter.WhereClause = "objectID<=" + DeleteNum;
            IFeatureCursor pFeatureCursor = PFeatureclass.Search(pQueryFilter, false);            IFeature pFeature = pFeatureCursor.NextFeature();
            while (pFeature != null)
            {
                pFeature.Delete();
                pFeature = pFeatureCursor.NextFeature();
            }
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pQueryFilter);
        }
2.  更新游标删除
private void Delete2(IFeatureClass PFeatureclass)
        {
            IQueryFilter pQueryFilter = new QueryFilterClass();
            pQueryFilter.WhereClause = "objectID<=" + DeleteNum;
            IFeatureCursor pFeatureCursor = PFeatureclass.Update(pQueryFilter, false);
            IFeature pFeature = pFeatureCursor.NextFeature();
            while (pFeature != null)
            {
                pFeatureCursor.DeleteFeature();
                pFeature = pFeatureCursor.NextFeature();
            }
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pQueryFilter);
 
        }
3.  使用DeleteSearchedRows删除
private void Delete4(IFeatureClass PFeatureclass)
        {
            IQueryFilter pQueryFilter = new QueryFilterClass();
            pQueryFilter.WhereClause = "objectID<=" + DeleteNum;
            ITable pTable = PFeatureclass as ITable;
            pTable.DeleteSearchedRows(pQueryFilter);
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pQueryFilter);
        }
 
4.  ExecuteSQL删除
private void Delete4(IFeatureClass PFeatureclass)
        {
            IDataset pDataset = PFeatureclass as IDataset;
            pDataset.Workspace.ExecuteSQL("delete from " + PFeatureclass.AliasName + " where objectid<=" + DeleteNum);
        }
二、  测试性能和比较
1、       相同的数据条件,删除2000条记录
2、       测试代码
IFeatureLayer pFeatureLayer = axMapControl1.Map.get_Layer(0) as IFeatureLayer;
            IFeatureClass PFeatureClass = pFeatureLayer.FeatureClass;
            System.Diagnostics.Stopwatch MyWatch = new System.Diagnostics.Stopwatch();
            MyWatch.Start();
            Delete1(PFeatureClass)
            //Delete2(PFeatureClass);
            //Delete3(PFeatureClass);
            //Delete4(PFeatureClass);
            //Delete5(PFeatureClass);
            MyWatch.Stop();
            MessageBox.Show("删除时间:" + MyWatch.ElapsedMilliseconds.ToString() + "毫秒");
3、       测试情况
测试方法
 第一次时间(单位ms)
 第一次时间(单位ms)
 
1
 5214ms
 5735ms
 
2
 299ms
 290Ms
 
3
 59ms
 28ms
 
4
 26ms
 26ms
 
三、  结论
1、         使用ExecuteSQL删除最快,数据库的效率最高。
2、         DeleteSearchedRows和ExecuteSQL属于批量删除,性能较优。
3、         查询结果中删除,速度最慢,如果你使用这种方法,建立你马上修改你的程序,因为你在浪费时间。
4、       小数据量记录数小于500000条,请使用DeleteSearchedRows或ExecuteSQL,否则使用更新游标删除(方法2),加上进度条,这样界面很友好。
您正在看的文章来自地信网论坛 http://bbs.3s001.com,原文地址:http://bbs.3s001.com/read.php?tid=2363.html