ArcGIS Explorer Component Help |
Index Constructor (String, array<String>[]()[]) |
Index Class Example See Also |
Initializes a new instance of the Index class which can be used to create a new named, composite (multi-column) index on disk
when it is added to the IndexCollection. This constructor only applies to file geodatabase tables and feature classes.
Namespace:
ESRI.ArcGISExplorer.DataAssembly: ESRI.ArcGISExplorer (in ESRI.ArcGISExplorer.dll) Version: 2.0.0.1500 (2.0.0.1500)
Syntax
C# |
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public Index( string indexName, string[] columnNames ) |
Visual Basic (Declaration) |
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Public Sub New ( _ indexName As String, _ columnNames As String() _ ) |
Parameters
- indexName
- Type: System..::.String
Name of the index.
- columnNames
- Type: array<
System..::.String
>[]()[]
An Array of column names on which to create the composite index.
Remarks
The following properties use their default values:
- IsUnique property is set to falseFalsefalsefalse (False in Visual Basic).
- IsAscending property is set to trueTruetruetrue (True in Visual Basic).
Examples
The code below demonstrates how to create a new composite index on three columns in a file geodatabase feature class.
A new Index object is created specifying the name of the index and the names of the columns
to index. The Index object is then added to the IndexCollection to create the index on disk. The properties of
the Index object are printed out, including the names of the columns which participate in the
index using the GetColumnNames method.
CopyC#
{ //Open the countries file geodatabase feature class Table countriesTable = Table.OpenFileGeodatabaseTable(@"C:\Data\World.gdb","countries"); //Get the IndexCollection IndexCollection indexes = countriesTable.Indexes; //Create string array of columns that will make up the composite index string[] columnsToIndex = {"Name", "Region", "Continent"}; //Create a new Index object Index compositeIndex = new Index("idx_Composite", columnsToIndex); try { //Add the Index to the IndexCollection thereby creating it on disk. indexes.Add(compositeIndex); //Print out the index properties System.Diagnostics.Debug.Print(compositeIndex.Name); //Prints "idx_Composite" System.Diagnostics.Debug.Print(compositeIndex.IsAscending.ToString()); //Prints "True" System.Diagnostics.Debug.Print(compositeIndex.IsUnique.ToString()); //Prints "False" foreach (string columnName in compositeIndex.GetColumnNames()) { System.Diagnostics.Debug.Print(columnName); } //Prints: //"Name" //"Region" //Continent } catch (Exception ex) { System.Diagnostics.Debug.Print(ex.Message); } }
CopyVB.NET
'Open the countries file geodatabase feature class Dim countriesTable As Table = Table.OpenFileGeodatabaseTable("C:\Data\World.gdb", "countries") 'Get the IndexCollection Dim indexes As IndexCollection = countriesTable.Indexes 'Create string array of columns that will make up the composite index Dim columnsToIndex As String() = {"Name", "Region", "Continent"} 'Create a new Index object Dim compositeIndex As Index = New Index("idx_Composite", columnsToIndex) Try 'Add the Index to the IndexCollection thereby creating it on disk. indexes.Add(compositeIndex) 'Print out the index properties System.Diagnostics.Debug.Print(compositeIndex.Name) 'Prints "idx_Composite" System.Diagnostics.Debug.Print(compositeIndex.IsAscending.ToString()) 'Prints "True" System.Diagnostics.Debug.Print(compositeIndex.IsUnique.ToString()) 'Prints "False" For Each columnName As String In compositeIndex.GetColumnNames() System.Diagnostics.Debug.Print(columnName) Next 'Prints: '"Name" '"Region" 'Continent Catch ex As Exception System.Diagnostics.Debug.Print(ex.Message) End Try