Real estate Database

i think this table names are not really intuitive especially with your illustration
i would prefer your first attempt because we don't have to much to fix here

your proprietati table need an adress id not an zone id because if you just know the zone you don't know which address it is
take zone -> strazi -> adrese and in proprietati make an id_adresa as relational field

the other thing which comes to mind is your strazi table; if you use one extra table for streets - you should think about a junction table between streets and zones because if your db grows you avoid duplicate street names

i don't understand the 2nd attempt at all - to much duplication

I come with an update for this post:

- I am trying to reduce duplicity but If I choose the first diagram and I need to get the address for a property I need the iterate through areas->streets>addresses . But with the second I have the address id in the main table.

Another problem I encounter.


I have a lot of characteristics for each of:

- apartments
- lands
- spaces
- houses

And when I add a land property for example all of apartments characteristics will be empty.

Initially I was thinking to create 4 more tables:

- apartments_characteristics
- lands_characteristics
- spaces_characteristics
- houses_characteristics


and when select a property to select from the specified table.

Here is the english version of the db



P.S. this db is on progress.