Creating, Altering, and Removing Indexes

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In the SQL Server Management Objects (SMO) hierarchy, indexes are represented by the Index object. The indexed columns are represented by a collection of IndexedColumn objects represented by the IndexedColumns property.

You can create an index on a XML column by specifying the IsXmlIndex property of the Index object.

Examples

To use any code example that is provided, you will have to choose the programming environment, the programming template, and the programming language in which to create your application. For more information, see Create a Visual Basic SMO Project in Visual Studio .NET or Create a Visual C# SMO Project in Visual Studio .NET.

Creating a Non-Clustered, Composite Index in Visual Basic

This code example demonstrates how to create a composite, non-clustered index. For a composite index, add more than one column to the index. Set the IsClustered property to False for a nonclustered index.

' /r:Microsoft.SqlServer.Smo.dll
' /r:Microsoft.SqlServer.ConnectionInfo.dll
' /r:Microsoft.SqlServer.SqlEnum.dll
' /r:Microsoft.SqlServer.Management.Sdk.Sfc.dll

Imports Microsoft.SqlServer.Management.Smo
Public Class A
    Public Shared Sub Main()
        ' Connect to the local, default instance of SQL Server. 
        Dim srv As Server
        srv = New Server()

        ' Reference the AdventureWorks2012 database. 
        Dim db As Database
        db = srv.Databases("AdventureWorks2012")

        ' Declare a Table object and reference the HumanResources table. 
        Dim tb As Table
        tb = db.Tables("Employee", "HumanResources")

        ' Define an Index object variable by providing the parent table and index name in the constructor. 
        Dim idx As Index
        idx = New Index(tb, "TestIndex")

        ' Add indexed columns to the index. 
        Dim icol1 As IndexedColumn
        icol1 = New IndexedColumn(idx, "BusinessEntityID", True)
        idx.IndexedColumns.Add(icol1)
        Dim icol2 As IndexedColumn
        icol2 = New IndexedColumn(idx, "HireDate", True)
        idx.IndexedColumns.Add(icol2)

        ' Set the index properties. 
        idx.IndexKeyType = IndexKeyType.DriUniqueKey
        idx.IsClustered = False
        idx.FillFactor = 50

        ' Create the index on the instance of SQL Server. 
        idx.Create()

        ' Modify the page locks property. 
        idx.DisallowPageLocks = True

        ' Run the Alter method to make the change on the instance of SQL Server. 
        idx.Alter()

        ' Remove the index from the table. 
        idx.Drop()
    End Sub
End Class

Creating a Non-Clustered, Composite Index in Visual C#

This code example demonstrates how to create a composite, non-clustered index. For a composite index, add more than one column to the index. Set the IsClustered property to False for a nonclustered index.

// /r:Microsoft.SqlServer.Smo.dll
// /r:Microsoft.SqlServer.ConnectionInfo.dll
// /r:Microsoft.SqlServer.SqlEnum.dll
// /r:Microsoft.SqlServer.Management.Sdk.Sfc.dll

using Microsoft.SqlServer.Management.Smo;

public class A {
   public static void Main() {
      // Connect to the local, default instance of SQL Server. 
      Server srv;
      srv = new Server();

      // Reference the AdventureWorks2012 database. 
      Database db;
      db = srv.Databases["AdventureWorks2012"];

      // Declare a Table object and reference the HumanResources table. 
      Table tb;
      tb = db.Tables["Employee", "HumanResources"];

      // Define an Index object variable by providing the parent table and index name in the constructor. 
      Index idx;
      idx = new Index(tb, "TestIndex");

      // Add indexed columns to the index. 
      IndexedColumn icol1;
      icol1 = new IndexedColumn(idx, "BusinessEntityID", true);
      idx.IndexedColumns.Add(icol1);
      IndexedColumn icol2;
      icol2 = new IndexedColumn(idx, "HireDate", true);
      idx.IndexedColumns.Add(icol2);

      // Set the index properties. 
      idx.IndexKeyType = IndexKeyType.DriUniqueKey;
      idx.IsClustered = false;
      idx.FillFactor = 50;

      // Create the index on the instance of SQL Server. 
      idx.Create();

      // Modify the page locks property. 
      idx.DisallowPageLocks = true;

      // Run the Alter method to make the change on the instance of SQL Server. 
      idx.Alter();

      // Remove the index from the table. 
      idx.Drop();
   }
}

Creating a Non-Clustered, Composite Index in PowerShell

This code example demonstrates how to create a composite, non-clustered index. For a composite index, add more than one column to the index. Set the IsClustered property to False for a nonclustered index.

# Set the path context to the local, default instance of SQL Server and to the
#database tables in Adventureworks2012
CD \sql\localhost\default\databases\AdventureWorks2012\Tables\

#Get a reference to the table
$tb = get-item HumanResources.Employee

#Define an Index object variable by providing the parent table and index name in the constructor. 
$idx = New-Object -TypeName Microsoft.SqlServer.Management.SMO.Index -argumentlist $tb, "TestIndex"

#Add indexed columns to the index. 
$icol1 = New-Object -TypeName Microsoft.SqlServer.Management.SMO.IndexedColumn `
-argumentlist $idx, "BusinessEntityId", $true
$idx.IndexedColumns.Add($icol1)

$icol2 = New-Object -TypeName Microsoft.SqlServer.Management.SMO.IndexedColumn `
-argumentlist $idx, "HireDate", $true
$idx.IndexedColumns.Add($icol2)

#Set the index properties. 
$idx.IndexKeyType = [Microsoft.SqlServer.Management.SMO.IndexKeyType]::DriUniqueKey 
$idx.IsClustered = $false
$idx.FillFactor = 50

#Create the index on the instance of SQL Server. 
$idx.Create()

#Modify the page locks property. 
$idx.DisallowPageLocks = $true

#Run the Alter method to make the change on the instance of SQL Server. 
$idx.Alter()

#Remove the index from the table. 
$idx.Drop();

Creating an XML Index in Visual Basic

This code example shows how to create an XML index on an XML data type. The XML data type is an XML schema collection called MySampleCollection, which is created in Using XML Schemas. XML indexes have some restrictions, one of which is that it must be created on a table that already has a clustered, primary key.

' /r:Microsoft.SqlServer.Smo.dll
' /r:Microsoft.SqlServer.ConnectionInfo.dll
' /r:Microsoft.SqlServer.SqlEnum.dll
' /r:Microsoft.SqlServer.Management.Sdk.Sfc.dll

Imports Microsoft.SqlServer.Management.Smo

Public Class A
    Public Shared Sub Main()
        ' Connect to the local, default instance of SQL Server. 
        Dim srv As Server
        srv = New Server()
        Dim db1 As Database = srv.Databases("TESTDB")
        ' Define a Table object variable and add an XML type column. 
        Dim tb As New Table(db1, "XmlTable3")

        Dim mySample As New XmlSchemaCollection(db1, "Sample4", "dbo")
        mySample.Text = "<xsd:schema xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" targetNamespace=""NS2""> <xsd:element name=""elem1"" type=""xsd:integer""/></xsd:schema>"
        mySample.Create()

        Dim col11 As Column

        ' This sample requires that an XML schema type called MySampleCollection exists on the database. 
        col11 = New Column(tb, "XMLValue", DataType.Xml("Sample4"))

        ' Add another integer column that can be made into a unique, primary key. 
        tb.Columns.Add(col11)
        Dim col21 As Column
        col21 = New Column(tb, "Number", DataType.Int)
        col21.Nullable = False
        tb.Columns.Add(col21)

        ' Create the table of the instance of SQL Server. 
        tb.Create()

        ' Create a unique, clustered, primary key index on the integer column. This is required for an XML index. 
        Dim cp As Index
        cp = New Index(tb, "clusprimindex3")
        cp.IsClustered = True
        cp.IndexKeyType = IndexKeyType.DriPrimaryKey
        Dim cpcol As IndexedColumn
        cpcol = New IndexedColumn(cp, "Number", True)
        cp.IndexedColumns.Add(cpcol)
        cp.Create()

        ' Define and XML Index object variable by supplying the parent table and the XML index name arguments in the constructor. 
        Dim i As Index
        i = New Index(tb, "xmlindex")
        Dim ic As IndexedColumn
        ic = New IndexedColumn(i, "XMLValue", True)
        i.IndexedColumns.Add(ic)

        ' Create the XML index on the instance of SQL Server. 
        i.Create()
    End Sub
End Class

Creating an XML Index in Visual C#

This code example shows how to create an XML index on an XML data type. The XML data type is an XML schema collection called MySampleCollection, which is created in Using XML Schemas. XML indexes have some restrictions, one of which is that it must be created on a table that already has a clustered, primary key.

// /r:Microsoft.SqlServer.Smo.dll
// /r:Microsoft.SqlServer.ConnectionInfo.dll
// /r:Microsoft.SqlServer.SqlEnum.dll
// /r:Microsoft.SqlServer.Management.Sdk.Sfc.dll

using Microsoft.SqlServer.Management.Smo;

public class A {
   public static void Main() {
      // Connect to the local, default instance of SQL Server. 
      Server srv;
      srv = new Server();
      Database db1 = srv.Databases["TESTDB"];
      // Define a Table object variable and add an XML type column. 
      Table tb = new Table(db1, "XmlTable3");

      XmlSchemaCollection mySample = new XmlSchemaCollection(db1, "Sample4", "dbo");
      mySample.Text = "<xsd:schema xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" targetNamespace=\"NS2\"> <xsd:element name=\"elem1\" type=\"xsd:integer\"/></xsd:schema>";
      mySample.Create();

      Column col11;

      // This sample requires that an XML schema type called MySampleCollection exists on the database. 
      col11 = new Column(tb, "XMLValue", DataType.Xml("Sample4"));

      // Add another integer column that can be made into a unique, primary key. 
      tb.Columns.Add(col11);
      Column col21;
      col21 = new Column(tb, "Number", DataType.Int);
      col21.Nullable = false;
      tb.Columns.Add(col21);

      // Create the table of the instance of SQL Server. 
      tb.Create();

      // Create a unique, clustered, primary key index on the integer column. This is required for an XML index. 
      Index cp;
      cp = new Index(tb, "clusprimindex3");
      cp.IsClustered = true;
      cp.IndexKeyType = IndexKeyType.DriPrimaryKey;
      IndexedColumn cpcol;
      cpcol = new IndexedColumn(cp, "Number", true);
      cp.IndexedColumns.Add(cpcol);
      cp.Create();

      // Define and XML Index object variable by supplying the parent table and the XML index name arguments in the constructor. 
      Index i;
      i = new Index(tb, "xmlindex");
      IndexedColumn ic;
      ic = new IndexedColumn(i, "XMLValue", true);
      i.IndexedColumns.Add(ic);

      // Create the XML index on the instance of SQL Server. 
      i.Create();
   }
}

Creating an XML Index in PowerShell

This code example shows how to create an XML index on an XML data type. The XML data type is an XML schema collection called MySampleCollection, which is created in Using XML Schemas. XML indexes have some restrictions, one of which is that it must be created on a table that already has a clustered, primary key.

# Set the path context to the local, default instance of SQL Server and get a reference to adventureworks2012
CD \sql\localhost\default\databases
$db = get-item Adventureworks2012

#Define a Table object variable and add an XML type column. 
#This sample requires that an XML schema type called MySampleCollection exists on the database. 
#See sample on Creating an XML schema to do this
$tb = New-Object -TypeName Microsoft.SqlServer.Management.SMO.Table -argumentlist $db, "XmlTable"
$Type = [Microsoft.SqlServer.Management.SMO.DataType]::Xml("MySampleCollection")
$col1 =  New-Object -TypeName Microsoft.SqlServer.Management.SMO.Column -argumentlist $tb,"XMLValue", $Type
$tb.Columns.Add($col1)

#Add another integer column that can be made into a unique, primary key. 
$Type = [Microsoft.SqlServer.Management.SMO.DataType]::Int
$col2 =  New-Object -TypeName Microsoft.SqlServer.Management.SMO.Column -argumentlist $tb,"Number", $Type
$col2.Nullable = $false
$tb.Columns.Add($col2)
          
#Create the table of the instance of SQL Server. 
$tb.Create()

#Create a unique, clustered, primary key index on the integer column. This is required for an XML index. 
#Define an Index object variable by providing the parent table and index name in the constructor. 
$cp = New-Object -TypeName Microsoft.SqlServer.Management.SMO.Index -argumentlist $tb, "clusprimindex"        
$cp.IsClustered = $true;
$cp.IndexKeyType = [Microsoft.SqlServer.Management.SMO.IndexKeyType]::DriPrimaryKey;

#Create and add an indexed column to the index. 
$cpcol = New-Object -TypeName Microsoft.SqlServer.Management.SMO.IndexedColumn `
-argumentlist $cp, "Number", $true
$cp.IndexedColumns.Add($cpcol)
$cp.Create()

#Define and XML Index object variable by supplying the parent table and
# the XML index name arguments in the constructor. 
$i = New-Object -TypeName Microsoft.SqlServer.Management.SMO.Index -argumentlist $tb, "xmlindex" 

#Create and add an indexed column to the index. 
$ic = New-Object -TypeName Microsoft.SqlServer.Management.SMO.IndexedColumn `
-argumentlist $i, "XMLValue", $true  
$i.IndexedColumns.Add($ic)

#Create the XML index on the instance of SQL Server
$i.Create()

See Also

Reference

Index