@sin_dragan Hi dragan! Thank you!
Yes you're right, I used Zeos components. For Oracle, in database property of zconnection I put the whole server descriptor (same that is in ORA TNS File), I've also included ora light client libs so you don't need Oracle Client installed on client machine. Installed files can also be packed into a zip and it will work, you can take it with you in your usb stick memory, especially useful when someone needs to go to some client but has no access to install any sql manager in client's client machine, so one could use this tool to query and browse DBs.