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Note that the page button is labeled Year. Selecting one of All, 1998, or 1997 from the drop-down

list box next to this button will confine the data to that selection. Thus, the pivot table has three

pages: 1997, 1998, and combined (or All).

Note also that the columns are labeled by periods and the rows are labeled by both Store City and

Store Type, as requested. In addition, Excel has created a new field called Data that is used as row

labels. In this case, Excel correctly guessed that we want sums, but if Excel had guessed

incorrectly we could make a change manually.

In summary, we can see that the main components of a pivot table are the pages, rows, columns,

and data fields.

Rather than pursue further development of this PivotTable using the Excel interface, let us now

switch to using code.



20.3 The PivotTableWizard Method

To create a PivotTable through code, we use the PivotTableWizard method of the Worksheet

object or the PivotTable object. Contrary to what you might assume, the PivotTableWizard

method does not start the PivotTable wizard. Rather, it is used to create a PivotTable when applied

to the Worksheet object or to modify an existing PivotTable when applied to the PivotTable object.

The syntax is:

expression.PivotTableWizard(SourceType, SourceData, TableDestination, _

TableName, RowGrand, ColumnGrand, SaveData, HasAutoFormat, _

AutoPage, Reserved, BackgroundQuery, OptimizeCache, _

PageFieldOrder, ageFieldWrapCount, ReadData, Connection)



where expression returns either a Worksheet object or a PivotTable object. As you might

expect, the parameters of the PivotTableWizard method correspond to settings in the PivotTable

wizard. On the other hand, the PivotTableWizard method cannot do everything that the PivotTable



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wizard can do. For instance, it cannot be used to specify the row, column, and data fields. (We

will see how to do that a bit later.) Put another way, the PivotTableWizard method sets the

properties of an empty PivotTable.

Let us go over some of the more important parameters to the PivotTableWizard method.

The optional SourceType parameter specifies the source of the PivotTable data and can be one

of the following XlPivotTableSourceType constants:

Enum XlPivotTableSourceType

xlPivotTable = -4148

xlDatabase = 1

xlExternal = 2

xlConsolidation = 3

End Enum



These directly correspond to the first dialog of the PivotTable wizard, as shown in Figure 20-1.



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If we specify a value for SourceType, then we must also specify a value for SourceData. If

we specify neither, Excel uses the source type xlDatabase and the source data from a named

range called Database. If this named range does not exist, Excel uses the current region if the

current selection is in a range of more than 10 cells that contain data. Otherwise, the method will

fail. All in all, this rule is sufficiently complicated to warrant always specifying these parameters.

The SourceData parameter specifies the data for the PivotTable. It can be a Range object, an

array of ranges, or a text constant that represents the name of another PivotTable. For external data,

this must be a two-element array, the first element of which is the connection string specifying the

ODBC source for the data, and the second element of which is the SQL query string used to get

the data.



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The TableDestination parameter is a Range object specifying where the PivotTable should

be placed. It can include a worksheet qualifier to specify the worksheet upon which to place the

pivot table as well.

The TableName parameter is a string that specifies the name of the new PivotTable.

The RowGrand parameter should be set to True to show grand totals for rows in the PivotTable.

Similarly, the ColumnGrand parameter should be set to True to show grand totals for columns

in the PivotTable.

The SaveData parameter should be set to True to save data with the PivotTable. If it is False,

then only the PivotTable definition is saved.

HasAutoFormat is set to True to have Excel automatically format the PivotTable whenever it is

refreshed or whenever any fields are moved.



The PageFieldOrder and PageFieldWrapCount parameters are meaningful only when

there is more than one page field, in which case these parameters specify where the page field

buttons and concomitant drop-down list boxes are placed relative to one another. The

PageFieldOrder parameter can be either xlDownThenOver (the default) or

xlOverThenDown. For instance, if there were three page fields, then the setting:

PageFieldOrder = xlDownThenOver

PageFieldWrapCount = 2



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would arrange the page fields as in Figure 20-7. This pivot table is only for illustration of the page

field order. It was created from the original pivot table by moving the row fields to page fields.

Note also that setting PageFieldOrder to xlOverThenDown would simply reverse the

positions of Store City and Store Type.

Figure 20-7. Illustrating page field order



The following code ostensibly creates the PivotTable in Figure 20-6 at the location of the active

cell:

ActiveSheet.PivotTableWizard _

SourceType:=xlDatabase, _

SourceData:="'Source'!R1C1:R145C7", _

TableName:="Sales&Trans"



In fact, the results of executing this code are shown in Figure 20-8. The reason nothing much

seems to have happened is that, as we mentioned earlier, the PivotTableWizard method does not

allow us to specify which fields are page, row, column, and data fields. The table in Figure 20-8 is

an empty PivotTable.

Figure 20-8. An empty PivotTable



20.4 The PivotTable Object

To understand better what must be done next, we must discuss the PivotTable object and its

various child collection objects.

Invoking the PivotTableWizard method has created a PivotTable object named Sales&Trans for us.

All PivotTable objects have a PivotFields collection, accessed through the PivotFields property.

Thus, the code:

Dim pf As PivotField

For Each pf In _

ActiveSheet.PivotTables("Sales&Trans").PivotFields

Debug.Print pf.Name

Next



produces the following list of pivot fields:



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Year

Period

Store Code

Store City

Store Type

Transactions

Sales



Now, each PivotField object can have a designation that specifies whether this field is to be used

as a row field, a column field, a page field, or a data field. This designation is referred to as its

orientation.

It turns out that there is more than one way to set the orientation of a pivot field. One approach is

to set the pivot field's Orientation property, and another approach is to use the AddFields method.

Unfortunately, neither of these methods is sufficiently documented, so some experimentation is in

order.

As to the Orientation property approach, consider the code in Example 20-1, which sets both the

Orientation and Position properties. We will discuss the subtleties of this code after you have

looked at it.

Example 20-1. The CreatePivotFields Procedure

Sub CreatePivotFields()

' Assume source for pivot table

' is in sheet named 'Source'

ActiveSheet.PivotTableWizard _

SourceType:=xlDatabase, _

SourceData:="'Source'!R1C1:R145C7", _

TableName:="PivotTable1"

With ActiveSheet.PivotTables("Sales&Trans")

Debug.Print "Before all:"

ShowFields

.PivotFields("Year").Orientation = xlPageField

.PivotFields("Year").Position = 1

.PivotFields("Store City").Orientation =

.PivotFields("Store City").Position = 1

.PivotFields("Store Type").Orientation =

.PivotFields("Store Type").Position = 2

.PivotFields("Period").Orientation =

Debug.Print "Before data fields:"

ShowFields

With .PivotFields("Transactions")

.Orientation = xlDataField

.Position = 1

End With

With .PivotFields("Sales")

.Orientation = xlDataField

.Position = 2

End With



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xlRowField



xlRowField



xlColumnField