Export MSSQL schema with PowerShell. This script will export your schema definitions for tables, stored procs, triggers, functions and views to .sql files

ExportSchema.ps1

<#
.SYNOPSIS
	Export schema for a database
.DESCRIPTION
	This script will export your schema definitions for tables, stored procs, triggers, functions and views to .sql files
.PARAMETER ServerName
	database server instance 
.PARAMETER DatabaseName
	You can specify a database name to only export single DB schema
.PARAMETER ScriptPath
	directory where scripts will be dumped to.  Relative paths are also ok
.PARAMETER RecursiveMode
	Use this switch to export schema for ALL user databases on a servername	

.EXAMPLE
	Dump scripts for single database:
    powershell ExportSchema.ps1 "SERVERNAME" "DATABASE" "C:\<YourOutputPath>"
	.\ExportSchema.ps1 -ServerName Contososerver -DatabaseName Adventureworks -ScriptPath C:\export
.EXAMPLE
    ----
.NOTES
 New features:
 	- created RecursiveMode to allow dumping all user databases on a server
	- added commandline parameters, so can be called as a powershell commandlet
	- changed logic to prevent creating of empty script files
	- change logic to filter out encrypted functions/procedures, so no need to check for null script data
	
	
.LINK 
	https://gist.github.com/cheynewallace/9558179
#>
param(
 [Parameter(Mandatory=$true)]  [string][ValidateNotNullOrEmpty()] $ServerName
,[Parameter(Mandatory=$false)] [string][ValidateNotNullOrEmpty()]  $DatabaseName
,[Parameter(Mandatory=$false)] [string][ValidateNotNullOrEmpty()] $ScriptPath = "."
,[Parameter(Mandatory=$false)] [switch] $RecursiveMode = $false
)

function GenerateDBScript([Microsoft.SqlServer.Management.SMO.Database] $database, [string]$scriptPath)
{
  $scr = New-Object "Microsoft.SqlServer.Management.Smo.Scripter"
  $deptype = New-Object "Microsoft.SqlServer.Management.Smo.DependencyType"
  $scr.Server = $database.Parent
  $literalpath = convert-path -Path $scriptPath
 
  $options = New-Object "Microsoft.SqlServer.Management.SMO.ScriptingOptions"
  $options.AllowSystemObjects = $false
  $options.IncludeDatabaseContext = $true
  $options.IncludeIfNotExists = $false
  $options.ClusteredIndexes = $true
  $options.Default = $true
  $options.DriAll = $true
  $options.Indexes = $true
  $options.NonClusteredIndexes = $true
  $options.IncludeHeaders = $false
  $options.ToFileOnly = $true
  $options.AppendToFile = $true
  $options.ScriptDrops = $false 
  $options.Encoding = $Encoding

  # Set options for SMO.Scripter
  $scr.Options = $options

  #=============
  # Tables
  #=============  
  $tables = $database.Tables | where {$_.IsSystemObject -eq $false}
  if ( $tables.Count -gt 0 )
  {
  	$options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_tables.sql"
  	New-Item $options.FileName -type file -force | Out-Null
  	Write-verbose "initalizing $($options.Filename)"
  	Foreach ($tb in $database.Tables)
    {
    	If ($tb.IsSystemObject -eq $FALSE)
		{
    		$smoObjects = New-Object Microsoft.SqlServer.Management.Smo.UrnCollection
    		$smoObjects.Add($tb.Urn)
    		$scr.Script($smoObjects)
   		}
  	}
  }

  #=============
  # Views
  #=============  
  $views = $database.Views | where {$_.IsSystemObject -eq $false}
  if ( $($views).Count -gt 0 )
  {
	$options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_views.sql"
	New-Item $options.FileName -type file -force | Out-Null
	Write-verbose "initalizing $($options.Filename)"
  	Foreach ($view in $views)
  	{
		$scr.Script($view)
	}
  }

  #=============
  # StoredProcedures
  #=============  
  $StoredProcedures = $database.StoredProcedures | where {$_.IsSystemObject -eq $false -and $_.IsEncrypted -eq $false} 
  if ( $($StoredProcedures).Count -gt 0 )
  {
  	$options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_stored_procs.sql"
	New-Item $options.FileName -type file -force | Out-Null
	Write-verbose "initalizing $($options.Filename)"
  	Foreach ($StoredProcedure in $StoredProcedures)
	{
		$scr.Script($StoredProcedure)
	}
  } 
  #=============
  # Functions
  #=============  
  $UserDefinedFunctions = $database.UserDefinedFunctions |where {$_.IsSystemObject -eq $false -and $_.IsEncrypted -eq $false} 
  if ( $($UserDefinedFunctions).Count -gt 0 )
  {
  	$options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_functions.sql"
  	New-Item $options.FileName -type file -force | Out-Null
  	Write-verbose "initalizing $($options.Filename)"
	  	foreach ($function in $UserDefinedFunctions)
	  	{
			$scr.Script($function)
		}
  } 

  #=============
  # DBTriggers
  #=============
  $DBTriggers = $database.Triggers |where {$_.IsSystemObject -eq $false -and $_.IsEncrypted -eq $false} 
  if ( $($DBTriggers).Count -gt 0 )
	{
	$options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_db_triggers.sql"
	New-Item $options.FileName -type file -force | Out-Null
	Write-verbose "initalizing $($options.Filename)"
  		foreach ($trigger in $database.triggers)
  		{
    		$scr.Script($trigger)
  		}	
	}
  #=============
  # Table Triggers
  #=============
  $options.FileName = Join-Path $literalpath "$($servername)_$($database.Name)_table_triggers.sql"
  New-Item $options.FileName -type file -force | Out-Null
	foreach ($tb in $database.Tables)
  	{     
    	if($($tb.triggers).Count -gt 0)
    	{
      		foreach ($trigger in $tb.triggers)
      		{
        		$scr.Script($trigger)
      		}
    	}	
  	} 
}

#=============
# Execute
#=============
$VerbosePreference = "Continue"
$ErrorActionPreference = "Stop"

#$Encoding = [system.Text.Encoding]::UTF8
$Encoding = [system.Text.Encoding]::ASCII

Write-Verbose "Checking scriptPath"
if (-not $(Test-Path -Path $ScriptPath)) 
{ 
	Write-Error -Exception ([System.IO.FileNotFoundException]::new("Unable to find path specified $ScriptPath")) -ErrorAction Stop
	#exit -1
}


if ( $($RecursiveMode -eq $false) -and -not $DatabaseName)
{ 
	Write-Error -Message "the DatabaseName parameter is missing and you are not running in RecursiveMode" -Category InvalidArgument   -ErrorAction Stop
	#exit -1
}

Write-Verbose "Checking servername connectivity"
#check connectivity to db server
$SqlConnection = New-Object System.Data.SqlClient.SqlConnection
$SqlConnection.ConnectionString = "Server = $Servername ; Database = tempdb; Integrated Security = True"
try {$SqlConnection.Open()} 
catch 
{
	Write-Error -Exception $($_.Exception) -ErrorAction Stop
	#exit -1
}
$SqlConnection.Close() 

# ok to load SMO objects
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SMO") | Out-Null
[System.Reflection.Assembly]::LoadWithPartialName("System.Data") | Out-Null
$srv = new-object "Microsoft.SqlServer.Management.SMO.Server" $serverName
$srv.SetDefaultInitFields([Microsoft.SqlServer.Management.SMO.View], "IsSystemObject")

if ($RecursiveMode -eq $true)
{
	#recursive mode
	#get list of databases
	$databases = $srv.Databases | where {$_.IsSystemObject -eq $false -and $_.isAccessible -eq $true}
	foreach ($d in $databases)
	 { GenerateDBScript -Database $d -ScriptPath $ScriptPath  }
}
else 
{ 
	$db = New-Object "Microsoft.SqlServer.Management.SMO.Database"
	$db = $srv.Databases[$DatabaseName]
	GenerateDBScript -Database $db -ScriptPath $ScriptPath }

Write-Verbose "Success!"