parseAndConnectToOracle.ps1

param($tnsnamesPath = 'c:\tns\tnsnames.ora',$username = 'user',$password = 'gotmehere', $connectionName = 'mustard', $query = 'Select sysdate from dual')
$simplySQLPath = (Get-Module -ListAvailable simplySQL).ModuleBase
if($simplySQLPath -and (test-path $tnsnamesPath -PathType Leaf) -and (![string]::IsNullOrEmpty($node)))
{
    [System.Reflection.Assembly]::LoadFile("$simplySQLPath\DataReaderToPSObject.dll") | OUT-NULL
    Import-Module SimplySql -Force
    $parsedTN = (get-content $tnsnamesPath -raw)  -replace '(.*\=.*|\n.*\=)(.*|\n.*)\(DESCRIPTION*.\=' ,'Data Source = (DESCRIPTION ='  
    $splitTN = $parsedTN -split '(?=.*Data Source = \(DESCRIPTION \=)' 
    $tnsnames = $splitTN |?{$_ -like "*$connectionName*"}
    $connstring = "$tnsnames;User Id=$username;Password=$password"
    try
    {
        Open-OracleConnection -ConnectionString $connstring -ConnectionName $connectionName
        $result = Invoke-SqlQuery -ConnectionName $connectionName -Query "$SQLQuery"
        Close-SqlConnection -ConnectionName $connectionName
    }
    catch
    {
        $_.exception
    }

}
Else
{
    if(!(test-path $tnsnamesPath -PathType Leaf -ErrorAction Ignore))
    {
        Throw "Check TNSnamesPath:  $tnsNamesPath"
    }
    else
    {
        Throw "Exeception SIMPLYSQL not found in module Path $($env:PSModulePath)"
    }
}
$result

tnsnames.ora

ketchup=(DESCRIPTION =
                (ADDRESS_LIST=
                                (ADDRESS = (PROTOCOL = TCP)(HOST = server3)(PORT = 1521))
                                (ADDRESS = (PROTOCOL = TCP)(HOST = server58)(PORT = 1521)))
                (LOAD_BALANCE = YES)(CONNECTION_TIMEOUT=5)(RETRY_COUNT=3)
                (CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME = ketchup)
                (FAILOVER_MODE = (TYPE = SELECT)(METHOD = BASIC)(RETRIES = 180)(DELAY = 5)))
          )

mustard =
(DESCRIPTION =
	(ADDRESS_LIST =
		(ADDRESS = (PROTOCOL = TCP)(HOST = host1)(PORT = 1521))
		(ADDRESS = (PROTOCOL = TCP)(HOST = host2)(PORT = 1521))
		(LOAD_BALANCE = YES)(CONNECTION_TIMEOUT=5)(RETRY_COUNT=3)
		(FAILOVER = on)
	)
	(CONNECT_DATA =
	(SERVER = DEDICATED)
	(SERVICE_NAME = mustard)
	  (FAILOVER_MODE = (TYPE = SELECT)(METHOD = BASIC)(RETRIES = 180)(DELAY = 5))))
	  )
	)
	)
)