Query Oracle SQL DB using PowerShell and ODAC.NET (so no Oracle Client required). Associated blogpost https://blog.darrenjrobinson.com/using-powershell-to-query-oracle-dbs-without-using-the-oracle-client-oracle-data-provider-for-net/

OracleSQLQuery.ps1

# Path to ODAC.NET Installation
Add-Type -Path "c:\ODAC\odp.net\managed\common\Oracle.ManagedDataAccess.dll"

$reader = $false
# SQL DB Username, Password and DataSource Alias (as per tnsnames.ora)
$username = "SQLQueryUserName"
$password = "SQLUserPassword"
# Alias from TNSNames.ora
$datasource = "IDM"

$connectionstring = 'User Id=' + $username + ';Password=' + $password + ';Data Source=' + $datasource 
$queryStatment = "Select 'Hello world!' Greeting from dual"

try{
    $con = New-Object Oracle.ManagedDataAccess.Client.OracleConnection($connectionstring)
    $con.Open()

    $cmd = $con.CreateCommand()
    $cmd.CommandType = "text"
    $cmd.CommandText = $queryStatment

    $reader = $cmd.ExecuteReader()
    if ($reader.Read()) {
            $result = $reader.GetString(0)
            write-host -ForegroundColor Green $result 
        } else {
            write-host -ForegroundColor Yellow $result "nothing returned"
        }
    
} catch {
    Write-Error (“Database Exception: {0}`n{1}” -f `
        $con.ConnectionString, $_.Exception.ToString())
} finally{
    if ($con.State -eq ‘Open’) { $con.close() }
}