DataRecordset.GetPrimaryKey Method (Visio)
Gets the primary key setting and the name of the primary key column or columns for the data recordset.
This Visio object or member is available only to licensed users of Microsoft Visio Professional 2010 or Visio Premium 2010.
expression .GetPrimaryKey(PrimaryKeySettings, PrimaryKey())
expression An expression that returns a DataRecordset object.
Out parameter. The primary key setting for the data recordset. See Remarks for possible values.
Out parameter. An array of String variables.
You can use the GetPrimaryKey method to determine the existing primary key setting for a data recordset and the name of the primary key column or columns if a primary key has been specified. The method returns the primary key setting for the data recordset in the PrimaryKeySettings out parameter, as a value from the VisPrimaryKeySettings enumeration. The default (when no primary key has been specified) is visKeyRowOrder, which means that Microsoft Visio identifies data recordset rows by row order.
A data recordset for which a primary key has been specified can have single or composite primary key columns. A single-column primary key bases row identification on the values in a single column. A composite primary key uses two or more columns to identify a row uniquely. Possible values for PrimaryKeySettings are shown in this table.
Use row order as the primary key.
Use a single column as the primary key column.
Use multiple columns as primary key columns.
For the PrimaryKey() out parameter, pass a dimensionless array of strings. If the primary key setting returned is visKeySingle or visKeyComposite, the method also returns an array of primary key column name strings in the PrimaryKey() out parameter. If the primary key setting is visKeyRowOrder, the default, the method returns an empty array.
You can use the DataRecordset.SetPrimaryKey method to specify the primary key setting for the data recordset as well as the name of the column or columns that you want to set as the primary key column or columns. When you set primary keys, make sure that the column or columns you pick to be primary key columns contain unique values (or value sets) for each row.
This Microsoft Visual Basic for Applications (VBA) macro shows how you can use the GetPrimaryKey method to determine the primary key setting for a data recordset as well as the name of the first primary key column. The macro finds the most recently created data recordset associated with the document and, if a primary key has been specified, prints in the Immediate window the value of the primary key setting and the name of the first primary key column for the data recordset. If no primary key exists, it prints the primary key setting and the statement "No primary key."
Before running this macro, create at least one data recordset in the current document and, if you want, specify a primary key by using the SetPrimaryKey method.
Public Sub GetPrimaryKey_Example() Dim vsoDataRecordset As Visio.DataRecordset Dim intCount As Integer Dim astrPrimaryKeyColumns() As String Dim vsoKeySettings As VisPrimaryKeySettings intCount = ThisDocument.DataRecordsets.Count Set vsoDataRecordset = ThisDocument.DataRecordsets(intCount) vsoDataRecordset.GetPrimaryKey vsoKeySettings, astrPrimaryKeyColumns If vsoKeySettings = visKeyRowOrder Then Debug.Print vsoKeySettings, "No primary key" Else Debug.Print vsoKeySettings, astrPrimaryKeyColumns(0) End If End Sub