Powershell send Email with multiple address and attachment - sql

Question

I have an Excel file that stores the locations of .sql and .csv and the email addresses to be sent. The field headers are "To" (email recipients), "Subject" (email subjects), "Query" (.sql paths), and "CSV" (.csv paths to be exported). I made a powershell script that will run the queries and then send the exported csv to corresponding email addresses.
It works now without problem but I have no idea how I could modify the script so I can add this function; some recipients don't want to receive multiple emails after the script -> One email with multiple csv results/attachments (so I can group all csv if they are belong to each address). For example, recipient alan#abc.com may receive email of query 1,2,3 (3 csv) according to the excel file. Do you have any suggestion on that? Thanks.
This is my script (it's a for loop and will check if there is any empty result):
#SQL/Mail
$SQLServer = '.\SQLEXPRESS'
$db = 'db'
$smtp = 'smtp.com'
$from = 'test-report#abc.com'
#variable
$var = Import-CSV C:\SQL\Var.csv
$lastmonth = (Get-Date).AddMonths(-1).ToString("MMMM")
$logfilename = $(get-date -f yyyy-MM-dd)
#starts
Start-Transcript -Path C:\SQL\log_$logfilename.txt
for ($i = 0; $i -lt $var.Count; ++$i){
#email subject
$subject = $var.Subject[$i] + ' of '+ $lastmonth
#status
Write-Host "Running" $var.Subject[$i]
#query execution
$result = Invoke-Sqlcmd -InputFile $var.Query[$i] -ServerInstance $SQLServer -Database $db -OutVariable sqlReturn
#check if the result is empty
$is_empty = ($result).count
if($is_empty -eq 0){
Write-Host $var.Subject[$i] "has empty Result"
Send-MailMessage -From $from -To $var.To[$i] -Subject $subject -Body 'Empty' -Priority High -DeliveryNotificationOption OnSuccess, OnFailure -SmtpServer $smtp #send message without attachment
Write-Host "Sending Email"
}
else{
$result | Export-Csv -NoTypeInformation -Path $var.CSV[$i] -Encoding UTF8 #result export to csv
Send-MailMessage -From $from -To $var.To[$i] -Subject $subject -Body $lastmonth -Attachments $var.CSV[$i] -Priority High -DeliveryNotificationOption OnSuccess, OnFailure -SmtpServer $smtp #send with csv
Write-Host "Sending Email"
}
}
#finished loop
Write-Host "Finished"
Stop-Transcript