---

CREATE TABLE artists (
    artist_id INTEGER PRIMARY KEY,
    full_name TEXT,
    country TEXT
);

CREATE TABLE artworks (
    artwork_id INTEGER PRIMARY KEY,
    title TEXT,
    artist_id INTEGER,
    year_created INTEGER,
    start_price REAL,
    FOREIGN KEY (artist_id) REFERENCES artists(artist_id)
);

CREATE TABLE auctions (
    auction_id INTEGER PRIMARY KEY,
    auction_name TEXT,
    auction_date DATE
);

CREATE TABLE bidders (
    bidder_id INTEGER PRIMARY KEY,
    full_name TEXT,
    phone TEXT
);

CREATE TABLE employees (
    employee_id INTEGER PRIMARY KEY,
    full_name TEXT,
    position TEXT
);

CREATE TABLE bids (
    bid_id INTEGER PRIMARY KEY,
    artwork_id INTEGER,
    auction_id INTEGER,
    bidder_id INTEGER,
    bid_amount REAL,
    FOREIGN KEY (artwork_id) REFERENCES artworks(artwork_id),
    FOREIGN KEY (auction_id) REFERENCES auctions(auction_id),
    FOREIGN KEY (bidder_id) REFERENCES bidders(bidder_id)
);

CREATE TABLE sales (
    sale_id INTEGER PRIMARY KEY,
    artwork_id INTEGER,
    bidder_id INTEGER,
    employee_id INTEGER,
    sale_price REAL,
    sale_date DATE,
    FOREIGN KEY (artwork_id) REFERENCES artworks(artwork_id),
    FOREIGN KEY (bidder_id) REFERENCES bidders(bidder_id),
    FOREIGN KEY (employee_id) REFERENCES employees(employee_id)
);

INSERT INTO artists VALUES
(1,'Иван Петров','Россия'),
(2,'Анна Смирнова','Россия'),
(3,'John Smith','США'),
(4,'Maria Lopez','Испания'),
(5,'Pierre Martin','Франция');

INSERT INTO artworks VALUES
(1,'Закат',1,2020,5000),
(2,'Горы',1,2021,7000),
(3,'Портрет',2,2019,6000),
(4,'Река',2,2022,8000),
(5,'Forest',3,2018,5500),
(6,'Ocean',3,2020,7500),
(7,'Flowers',4,2021,6500),
(8,'Night City',4,2022,9000),
(9,'Village',5,2019,6200),
(10,'Sunrise',5,2023,9500);

INSERT INTO auctions VALUES
(1,'Весенний аукцион','2025-03-01'),
(2,'Летний аукцион','2025-06-15'),
(3,'Осенний аукцион','2025-09-20');

INSERT INTO bidders VALUES
(1,'Алексей Иванов','890100001'),
(2,'Мария Петрова','890100002'),
(3,'Дмитрий Сидоров','890100003'),
(4,'Ольга Кузнецова','890100004'),
(5,'Сергей Волков','890100005');

INSERT INTO employees VALUES
(1,'Елена Орлова','Менеджер'),
(2,'Игорь Павлов','Эксперт'),
(3,'Анна Белова','Администратор');

INSERT INTO bids VALUES
(1,1,1,1,5500),
(2,1,1,2,6000),
(3,2,1,3,7500),
(4,3,1,4,6500),
(5,4,1,5,8500),
(6,5,2,1,6000),
(7,6,2,2,8000),
(8,7,2,3,7000),
(9,8,2,4,9500),
(10,9,2,5,6800),
(11,10,3,1,10000),
(12,2,3,2,7800),
(13,3,3,3,6700),
(14,4,3,4,8800),
(15,5,3,5,6200);

INSERT INTO sales VALUES
(1,10,1,1,10000,'2025-09-20');