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  • ArcEngine数据删除几种方法和性能比较[转]

    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         DeleteSearchedRowsExecuteSQL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。

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  • 原文地址:https://www.cnblogs.com/HomeGIS/p/1509328.html
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