How to connect to an already existed user-password database table for authorization

I have anohter existed web system using a user-password table for authorization.
Now I want the owncloud to use the same user-password authorization settings.
How can I set up owncloud?


there is no such possibility included in ownCloud if its not one of the external user authentication methods listed here:

However you might find some apps providing additional external user authentication at the appstore:

Those are the possibilities to authenticate ownCloud users against an external system / user database.

To sum-up: You can't just hook ownCloud into an existing database scheme of another application. This would need an implementation on your own.