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Indexes Collection (DAO)

An Indexes collection contains all the stored Index objects of a TableDef object (Microsoft Access workspaces only).

Remarks

When you access a table-type Recordset object, use the object's Index property to specify the order of records. Set this property to the Name property setting of an existing Index object in the Indexes collection of the TableDef object underlying the Recordset object.

Note

You can use the Append or Delete method on an Indexes collection only if the Updatable property setting of the containing TableDef object is True.

After you create a new Index object, you should use the Append method to add it to the TableDef object's Indexes collection.

Important

Make sure your data complies with the attributes of your new index. If your index requires unique values, make sure that there are no duplicates in existing data records. If duplicates exist, the Microsoft Access database engine can't create the index; a trappable error results when you attempt to use the Append method on the new index.

Example

This example creates a new Index object, appends it to the Indexes collection of the Employees TableDef, and then enumerates the Indexes collection of the TableDef. Finally, it enumerates a Recordset, first using the primary Index, and then using the new Index. The IndexOutput procedure is required for this procedure to run.

Sub IndexObjectX() 
 
 Dim dbsNorthwind As Database 
 Dim tdfEmployees As TableDef 
 Dim idxNew As Index 
 Dim idxLoop As Index 
 Dim rstEmployees As Recordset 
 
 Set dbsNorthwind = OpenDatabase("Northwind.mdb") 
 Set tdfEmployees = dbsNorthwind!Employees 
 
 With tdfEmployees 
 ' Create new index, create and append Field 
 ' objects to its Fields collection. 
 Set idxNew = .CreateIndex("NewIndex") 
 
 With idxNew 
 .Fields.Append .CreateField("Country") 
 .Fields.Append .CreateField("LastName") 
 .Fields.Append .CreateField("FirstName") 
 End With 
 
 ' Add new Index object to the Indexes collection 
 ' of the Employees table collection. 
 .Indexes.Append idxNew 
 .Indexes.Refresh 
 
 Debug.Print .Indexes.Count & " Indexes in " & _ 
 .Name & " TableDef" 
 
 ' Enumerate Indexes collection of Employees 
 ' table. 
 For Each idxLoop In .Indexes 
 Debug.Print " " & idxLoop.Name 
 Next idxLoop 
 
 Set rstEmployees = _ 
 dbsNorthwind.OpenRecordset("Employees") 
 
 ' Print report using old and new indexes. 
 IndexOutput rstEmployees, "PrimaryKey" 
 IndexOutput rstEmployees, idxNew.Name 
 rstEmployees.Close 
 
 ' Delete new Index because this is a 
 ' demonstration. 
 .Indexes.Delete idxNew.Name 
 End With 
 
 dbsNorthwind.Close 
 
End Sub 
 
Sub IndexOutput(rstTemp As Recordset, _ 
 strIndex As String) 
 ' Report function for FieldX. 
 
 With rstTemp 
 ' Set the index. 
 .Index = strIndex 
 .MoveFirst 
 Debug.Print "Recordset = " & .Name & _ 
 ", Index = " & .Index 
 Debug.Print " EmployeeID - Country - Name" 
 
 ' Enumerate the recordset using the specified 
 ' index. 
 Do While Not .EOF 
 Debug.Print " " & !EmployeeID & " - " & _ 
 !Country & " - " & !LastName & ", " & !FirstName 
 .MoveNext 
 Loop 
 
 End With 
 
End Sub 

This example uses the CreateIndex method to create two new Index objects and then appends them to the Indexes collection of the Employees TableDef object. It then enumerates the Indexes collection of the TableDef object, the Fields collection of the new Index objects, and the Properties collection of the new Index objects. The CreateIndexOutput function is required for this procedure to run.

Sub CreateIndexX() 
 
 Dim dbsNorthwind As Database 
 Dim tdfEmployees As TableDef 
 Dim idxCountry As Index 
 Dim idxFirstName As Index 
 Dim idxLoop As Index 
 
 Set dbsNorthwind = OpenDatabase("Northwind.mdb") 
 Set tdfEmployees = dbsNorthwind!Employees 
 
 With tdfEmployees 
 ' Create first Index object, create and append Field 
 ' objects to the Index object, and then append the 
 ' Index object to the Indexes collection of the 
 ' TableDef. 
 Set idxCountry = .CreateIndex("CountryIndex") 
 With idxCountry 
 .Fields.Append .CreateField("Country") 
 .Fields.Append .CreateField("LastName") 
 .Fields.Append .CreateField("FirstName") 
 End With 
 .Indexes.Append idxCountry 
 
 ' Create second Index object, create and append Field 
 ' objects to the Index object, and then append the 
 ' Index object to the Indexes collection of the 
 ' TableDef. 
 Set idxFirstName = .CreateIndex 
 With idxFirstName 
 .Name = "FirstNameIndex" 
 .Fields.Append .CreateField("FirstName") 
 .Fields.Append .CreateField("LastName") 
 End With 
 .Indexes.Append idxFirstName 
 
 ' Refresh collection so that you can access new Index 
 ' objects. 
 .Indexes.Refresh 
 
 Debug.Print .Indexes.Count & " Indexes in " & _ 
 .Name & " TableDef" 
 
 ' Enumerate Indexes collection. 
 For Each idxLoop In .Indexes 
 Debug.Print " " & idxLoop.Name 
 Next idxLoop 
 
 ' Print report. 
 CreateIndexOutput idxCountry 
 CreateIndexOutput idxFirstName 
 
 ' Delete new Index objects because this is a 
 ' demonstration. 
 .Indexes.Delete idxCountry.Name 
 .Indexes.Delete idxFirstName.Name 
 End With 
 
 dbsNorthwind.Close 
 
End Sub 
 
Function CreateIndexOutput(idxTemp As Index) 
 
 Dim fldLoop As Field 
 Dim prpLoop As Property 
 
 With idxTemp 
 ' Enumerate Fields collection of Index object. 
 Debug.Print "Fields in " & .Name 
 For Each fldLoop In .Fields 
 Debug.Print " " & fldLoop.Name 
 Next fldLoop 
 
 ' Enumerate Properties collection of Index object. 
 Debug.Print "Properties of " & .Name 
 For Each prpLoop In .Properties 
 Debug.Print " " & prpLoop.Name & " - " & _ 
 IIf(prpLoop = "", "[empty]", prpLoop) 
 Next prpLoop 
 End With 
 
End Function