[Koha-devel] Horizon to Koha migration

Hello, has someone experience, or provide me with documentation, with what one must do, in order to make a migration, from Horizon to Koha? We have access only to a Horizon database, so we can only run sql queries, and we must get back, as much as possible info needed. I know the Koha part, i lack the knowledge, of how to extract info from Horizon, what tables exist, what info they have, how combine tables, etc Thank you very much