Finding ConfigMgr SQL Server with Powershell

$sccmsrv=  "CM01" 

$site = (gwmi -ComputerName $sccmsrv -Namespace root\sms `
   -Class SMS_ProviderLocation).sitecode  
    
# enumerating SQL server name for the given SCCM site server  
$sccmCompquery = gwmi -q "Select distinct SiteSystem, Role, `
   SiteCode FROM SMS_SiteSystemSummarizer where role = `
  'SMS SQL Server' and siteCode = '$site' ORDER BY SiteCode" `
  -namespace "root\sms\site_$site" -ComputerName $sccmsrv  

[string]$tmpstr = `
   [regex]::Match($sccmCompquery.sitesystem, "\\\\w+\\$") 

$tmpstr = ($sccmCompquery.SiteSystem).SubString([regex]::Match( `
   $sccmCompquery.SiteSystem, "]\\").Index + 3)

$sccmSQLServer = $tmpstr.replace("\", "")

$sccmDB = "CM_$site"