Command Behavior

I get the error " 'commandBehavior' not declared". What does this mean? What is CommandBehavior exactly?

'
Sub Page_Load(Sender As Object, e As EventArgs)

' Obtain categoryId from QueryString
Dim connectionString As String = "server=(local); trusted_connection=true; database=SalesSide"
Dim sqlConnection As System.Data.SqlClient.SqlConnection = New System.Data.SqlClient.SqlConnection(connectionString)

Dim queryString As String = "Select tblIdent.fldStockNo, tblIdent.fldProgram, tblIdent.fldGenus" & _
"tblIdent.fldVariety, tblIdent.fldSize, tblAvailability.fldQuantity" & _
"FROM tblIdent INNER JOIN tblIdent On tblAvailability.fldStockNo = tblIdent.fldStockNo"

Dim sqlCommand As System.Data.SqlClient.SqlCommand = New System.Data.SqlClient.SqlCommand(queryString, sqlConnection)

sqlConnection.Open

dgAvailability.DataSource = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection)
dgAvailability.DataBind()

sqlConnection.Close

End SubIf you do not include the namespace System.Data you must explicitly reference all classes contained in it, including CommandBehavior.