Delete Empty Components

Description:

This script will delete empty components from a Windows Installer.

Usage

CScript.exe {Script} {MSI}

Script

'set up log file
Dim fso : Set fso = CreateObject("Scripting.FileSystemObject")
Const ForReading = 1
Const ForWriting = 2
Const ForAppending = 8

'create a name/path for log file
Dim MSIPath : Set MSIPath = fso.GetFile(WScript.Arguments(0))  
Dim logFile : logFile = Left(MSIPath.Path, InStrRev(MSIPath.Path, ".") - 1) & ".log"

Dim objLogFile : Set objLogFile = fso.OpenTextFile(logFile, ForAppending, True)

WriteLog "Deleting Empty Components"
WriteLog "Processing: " & MSIPath.Name

'create 2 constants - one for when we want to just query the MSI (read) and one for when we want to make changes (write)

Const msiOpenDatabaseModeReadOnly = 0
Const msiOpenDatabaseModeTransact = 1

'create WindowsInstaller.Installer object
Dim oInstaller : Set oInstaller = CreateObject("WindowsInstaller.Installer")

'open the MSI (the first argument supplied to the vbscript)
Dim oDatabase : Set oDatabase = oInstaller.OpenDatabase(WScript.Arguments(0),msiOpenDatabaseModeTransact) 

Dim componentsView, componentsRec, tableView, tableRec, dataView, dataRec

Dim emptyComponent : emptyComponent = True
Dim tempComponent : tempComponent = ""

If oDatabase.TablePersistent("Component") = 1 Then

	Set componentsView = oDatabase.OpenView("Select `Component` From `Component` ORDER BY `Component`")
	componentsView.Execute
	Set componentsRec = componentsView.Fetch
	Do While Not componentsRec is Nothing

		tempComponent = componentsRec.StringData(1)
                emptyComponent = True

		'list the tables that have 'Component_' (foreign key) columns
		Set tableView = oDatabase.OpenView("SELECT `Table` FROM `_Columns` WHERE `Name`= 'Component_' AND `Table` <> 'FeatureComponents'") 
		tableView.Execute
		Set tableRec = tableView.Fetch
		Do While Not tableRec is Nothing
			
			Set dataView = oDatabase.OpenView("SELECT  `Component_` FROM `" & tableRec.StringData(1) & "`  WHERE `Component_`='" & tempComponent & "'")
			dataView.Execute
			If Not dataView.Fetch is Nothing Then 'this table has a some data belonging to some component
				'component contains data
				emptyComponent = False
				'skip component and move to next
				Exit Do
			End If

			Set tableRec = tableView.Fetch
		Loop

		If emptyComponent Then
			'delete the empty component
			oDatabase.OpenView("DELETE FROM `Component` WHERE `Component` = '" & tempComponent & "'").Execute

			oDatabase.OpenView("DELETE FROM `FeatureComponents` WHERE `Component_` = '" & tempComponent & "'").Execute

			WriteLog "Deleting empty component: " & tempComponent
		End If

		Set componentsRec = componentsView.Fetch
	Loop

	Set tableRec = Nothing
	Set tableView = Nothing
	Set componentsView = Nothing
	Set componentsRec = Nothing
	Set dataView = Nothing

End If	

oDatabase.Commit

objLogFile.Close
Set fso = Nothing
Set objLogFile = Nothing	
Set oDatabase = Nothing
Set oInstaller = Nothing

Sub WriteLog(LogMessage)

	WScript.echo Now() & ": " & LogMessage
    objLogFile.Writeline(Now() & ": " & LogMessage)

End Sub