Get Site collection URL, Size, content database using powershell

<#
******-----------------------------------------------------------------------******
Author          -> Shiv Mangal Singh
Date            -> 9th March Jan - 2017
Description     -> THIS SCRIPT WILL GENERATE A REPORT TO GET Site collection URL, Site Collection Size, Sub Site URL and associated content database name.
Site Collection Name -->
******-----------------------------------------------------------------------******
 #>

Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue

Function GetUserAccessReport($WebAppURL, $FileUrl)
{
#Get All Site Collections of the WebApp
$SiteCollections = Get-SPSite -WebApplication $WebAppURL -Limit All

#Write CSV- TAB Separated File) Header
"Site Collection `t Site Coll Size in MB `t Sub Site `t Title `t Content DB " | out-file $FileUrl
 
  #Loop through all site collections
     foreach($Site in $SiteCollections)
       {

        # Get the Site Collection Size in MB.
         $sizeinKB =$Site.Usage.Storage
         $sizeinMB=$sizeinKB/1024/1024
         $sizeinMB = [Math]::Round($sizeinMB,2)
         Write-host $sizeinMB

       #Loop through all content datbase
        foreach($contentDB in $Site.ContentDatabase)
         {
          #Loop through all Sub Sites
           foreach($Web in $Site.AllWebs)
           {    
       
            "$($Site.RootWeb.Url)`t $($sizeinMB) `t $($Web.Url) `t $($Web.Title) `t $($contentDB) " | Out-File $FileUrl -Append
         
            }
          }
                                 
       }
}

#Call the function to Check User Access
GetUserAccessReport "https://Abc.com" D:\Tech\Report.csv"