moje:
CREATE TABLE [dbo].[Knihovna] (
    [KnihovnaID] INT         IDENTITY (1, 1) NOT NULL,
    [Jmeno]      NCHAR (100) NULL,
    PRIMARY KEY CLUSTERED ([KnihovnaID] ASC)
);


CREATE TABLE [dbo].[Oddeleni] (
    [OddeleniID] INT         IDENTITY (1, 1) NOT NULL,
    [Jmeno]      NCHAR (100) NULL,
    [KnihovnaID] INT         NULL,
    PRIMARY KEY CLUSTERED ([OddeleniID] ASC),
    FOREIGN KEY ([KnihovnaID]) REFERENCES [dbo].[Knihovna] ([KnihovnaID])
);


CREATE TABLE [dbo].[Kniha] (
    [KnihaID]    INT         IDENTITY (1, 1) NOT NULL,
    [Nazev]      NCHAR (100) NULL,
    [Autor]      NCHAR (100) NULL,
    [Zanr]       NCHAR (100) NULL,
    [Rok]        INT         NULL,
    [ISBN]       INT         NULL,
    [OddeleniID] INT         NULL,
    PRIMARY KEY CLUSTERED ([KnihaID] ASC),
    FOREIGN KEY ([OddeleniID]) REFERENCES [dbo].[Oddeleni] ([OddeleniID])
);


app a navod:
https://app.quickdatabasediagrams.com/#/
# Modify this code to update the DB schema diagram.
# To reset the sample schema, replace everything with
# two dots ('..' - without quotes).

Customer
-
CustomerID PK int
Name string INDEX
Address1 string
Address2 NULL string
Address3 NULL string

Order
-
OrderID PK int
CustomerID int FK >- Customer.CustomerID
TotalAmount money
OrderStatusID int FK >- os.OrderStatusID

OrderLine as ol
----
OrderLineID PK int
OrderID int FK >- Order.OrderID
ProductID int FK >- p.ProductID
Quantity int

# Table documentation comment 1 (try the PDF/RTF export)
Product as p # Table documentation comment 2
------------
ProductID PK int
# Field documentation comment 1
# Field documentation comment 2 
Name varchar(200) UNIQUE # Field documentation comment 3
Price money

OrderStatus as os
----
OrderStatusID PK int
Name UNIQUE string


moje:
Knihovna 
----------------------
KnihovnaID PK int
Jmeno string

Oddeleni
----
OddeleniID PK int
Jmeno string
KnihovnaID int FK >- Knihovna.KnihovnaID

Kniha
-
KnihaID PK int
Nazev string
Autor string
Zanr  string
Rok  int
ISBN int
OddeleniID int FK >- Oddeleni.OddeleniID