Trouble parsing SQL data with Powershell - powershell

Question

I have, what I think, is a real head-scratcher.
I am accessing a database to get a list of accounts. Each account has an account_id and account_parent_id property (among several other properties). If the account is the child of another account, the account_parent_id has the account ID of the parent and if the account is a parent (or has no children), the account_parent_id is blank. There are only two levels, so if an account has one or more children, it will not have a parent.
I need the output to be the account number (if the account has no children) and the account number of the parent and all children (comma separated) if there are children. Here is the code I have:
$SQLServer = "<database fqdn>"
$SQLDBName = "<databaes name>"
$uid ="<username>"
$pwd = "<password>"
$SqlQuery = "SELECT * from <account table>"
$SqlConnection = New-Object System.Data.SqlClient.SqlConnection
$SqlConnection.ConnectionString = "Server = $SQLServer; Database = $SQLDBName; Persist Security Info = True; User ID = $uid; Password = $pwd;"
$SqlConnection.Open()
$SqlCmd = New-Object System.Data.SqlClient.SqlCommand
$SqlCmd.CommandText = $SqlQuery
$SqlCmd.Connection = $SqlConnection
$SqlAdapter = New-Object System.Data.SqlClient.SqlDataAdapter
$SqlAdapter.SelectCommand = $SqlCmd
$DataSet = New-Object System.Data.DataSet
$SqlAdapter.Fill($DataSet)
$data = $DataSet[0].Tables
$SqlConnection.Close()
Foreach ($row in $data) {
Foreach ($account in $row) {
If ($account.parent_account_id -eq $row.account_id) {
$accts += $account.account_id
}
ElseIf ($account.parent_account_id -eq $account.account_id) {
$accts = $account.account_id
}
Return $accts
}
}
The problem is that I'm not getting anything at all into $accts. What am I missing here?
Thanks.

Answer 1

The best way to achieve your desired result is to do the mapping in SQL:
$SqlQuery = #'
SELECT t1.account_id AS parent, t2.account_id AS child
FROM <account table> t1 LEFT OUTER JOIN <account table> t2
ON t1.account_id = t2.parent_account_id
'#
Then you can extract the information you want via Group-Object and calculated properties:
$data | Group-Object parent |
Select-Object #{n='Parent';e={$_.Name}},
#{n='Children';e={$_.Group.child -join ','}}
If you're stuck with PowerShell v2 or earlier you need to replace $_.Group.child -join ',' with something like ($_.Group | Select-Object -Expand child) -join ','.

Answer 2

So, we did end up updating the SQL query. The data type I was getting back was a DataTable. I took out a row and used a loop like the following, to get he data I needed:
foreach ($item in $tableRow) {
$($item.account_ids)
}