= Креирање на базата


== DDL

```sql

CREATE TABLE "Event" (
    event_id BIGSERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    description TEXT NOT NULL,
    min_age INT NOT NULL
);

CREATE TABLE "Concert" (
    event_id BIGINT PRIMARY KEY,
    concert_type VARCHAR(50) NOT NULL,
    setlist TEXT NOT NULL,

    CONSTRAINT fk_concert_event FOREIGN KEY (event_id) REFERENCES "Event" (event_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);

CREATE TABLE "Play" (
    event_id BIGINT PRIMARY KEY,
    genre VARCHAR(50) NOT NULL,
    number_of_acts INT NOT NULL,
    language VARCHAR(50) NOT NULL,
    director VARCHAR(255) NOT NULL,

    CONSTRAINT fk_play_event FOREIGN KEY (event_id) REFERENCES "Event" (event_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);


CREATE TABLE "Performer" (
    performer_id BIGSERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    number_of_members INT NOT NULL,
    contact_email VARCHAR(255) NOT NULL UNIQUE,
    technical_requirements TEXT NOT NULL,

    CONSTRAINT performer_contact_email_check CHECK (contact_email ~ '^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$')
);

CREATE TABLE "Musical_Performer" (
    performer_id BIGINT PRIMARY KEY,
    musician_type VARCHAR(50) NOT NULL,
    genre VARCHAR(50) NOT NULL,
    record_label VARCHAR(255) NOT NULL,

    CONSTRAINT fk_musical_performer_performer FOREIGN KEY (performer_id) REFERENCES "Performer" (performer_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);

CREATE TABLE "Acting_Performer" (
    performer_id BIGINT PRIMARY KEY,
    role_type VARCHAR(50) NOT NULL,
    acting_style VARCHAR(100) NOT NULL,
    agency VARCHAR(255) NOT NULL,

    CONSTRAINT fk_acting_performer_performer FOREIGN KEY (performer_id) REFERENCES "Performer" (performer_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);


CREATE TABLE "Venue" (
    venue_id BIGSERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    number_of_sections INT NOT NULL,
    number_of_seats INT NOT NULL,
    address_street VARCHAR(255) NOT NULL,
    address_city VARCHAR(100) NOT NULL,
    address_country VARCHAR(100) NOT NULL
);

CREATE TABLE "Section" (
    section_id BIGSERIAL PRIMARY KEY,
    venue_id BIGINT NOT NULL,
    name VARCHAR(255) NOT NULL,
    number_of_seats INT NOT NULL,

    CONSTRAINT fk_section_venue FOREIGN KEY (venue_id) REFERENCES "Venue" (venue_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT uq_section_venue_name UNIQUE (venue_id, name)
);

CREATE TABLE "Seat" (
    seat_id BIGSERIAL PRIMARY KEY,
    section_id BIGINT NOT NULL,
    seat_number INT NOT NULL,

    CONSTRAINT fk_seat_section FOREIGN KEY (section_id) REFERENCES "Section" (section_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT uq_seat_section_number UNIQUE (section_id, seat_number)
);


CREATE TABLE "Organizer" (
    organizer_id BIGSERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    contact_email VARCHAR(255) NOT NULL UNIQUE,

    CONSTRAINT organizer_contact_email_check CHECK (contact_email ~ '^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$')
);

CREATE TABLE "Sponsor" (
    sponsor_id BIGSERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    contact_email VARCHAR(255) NOT NULL UNIQUE,
    sponsor_type VARCHAR(50) NOT NULL,

    CONSTRAINT sponsor_contact_email_check CHECK (contact_email ~ '^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$')
);


CREATE TABLE "Event_Happening" (
    event_happening_id BIGSERIAL PRIMARY KEY,
    event_id BIGINT NOT NULL,
    event_time TIMESTAMP NOT NULL,
    venue_id BIGINT NOT NULL,
    duration INT NOT NULL,

    CONSTRAINT fk_event_happening_event FOREIGN KEY (event_id) REFERENCES "Event" (event_id)
        ON DELETE RESTRICT
        ON UPDATE CASCADE,
    CONSTRAINT fk_event_happening_venue FOREIGN KEY (venue_id) REFERENCES "Venue" (venue_id)
        ON DELETE RESTRICT
        ON UPDATE CASCADE,
    CONSTRAINT uq_happening_time_venue UNIQUE (event_time, venue_id)
);

CREATE TABLE "Event_Period" (
    period_id BIGSERIAL PRIMARY KEY,
    event_happening_id BIGINT NOT NULL,
    name VARCHAR(255) NOT NULL,
    start_date DATE NOT NULL,
    end_date DATE NOT NULL,
    price_change_percent INT NOT NULL,
    increase_decrease BOOLEAN NOT NULL,

    CONSTRAINT fk_event_period_event_happening FOREIGN KEY (event_happening_id) REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT uq_period_happening_name UNIQUE (event_happening_id, name),
    CONSTRAINT event_period_dates_check CHECK (start_date <= end_date)
);


CREATE TABLE "Event_Happening_Performer" (
    event_happening_id BIGINT NOT NULL,
    performer_id BIGINT NOT NULL,

    CONSTRAINT pk_event_happening_performer PRIMARY KEY (event_happening_id, performer_id),
    CONSTRAINT fk_ehp_event_happening FOREIGN KEY (event_happening_id) REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT fk_ehp_performer FOREIGN KEY (performer_id) REFERENCES "Performer" (performer_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT uq_performer_at_time UNIQUE (performer_id, event_happening_id)
);

CREATE TABLE "Event_Happening_Organizer" (
    event_happening_id BIGINT NOT NULL,
    organizer_id BIGINT NOT NULL,

    CONSTRAINT event_happening_organizer PRIMARY KEY (event_happening_id, organizer_id),
    CONSTRAINT fk_eho_event_happening FOREIGN KEY (event_happening_id) REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT fk_eho_organizer FOREIGN KEY (organizer_id) REFERENCES "Organizer" (organizer_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);

CREATE TABLE "Event_Happening_Sponsor" (
    event_happening_id BIGINT NOT NULL,
    sponsor_id BIGINT NOT NULL,

    CONSTRAINT event_happening_sponsor PRIMARY KEY (event_happening_id, sponsor_id),
    CONSTRAINT fk_ehs_event_happening FOREIGN KEY (event_happening_id) REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT fk_ehs_sponsor FOREIGN KEY (sponsor_id) REFERENCES "Sponsor" (sponsor_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);


CREATE TABLE "User" (
    user_id BIGSERIAL PRIMARY KEY,
    username VARCHAR(50) NOT NULL UNIQUE,
    first_name VARCHAR(100) NOT NULL,
    last_name VARCHAR(100) NOT NULL,
    date_of_birth DATE NOT NULL,
    contact_email VARCHAR(255) NOT NULL UNIQUE,
    password VARCHAR(100) NOT NULL,
    registration_timestamp TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,

    CONSTRAINT user_date_of_birth_check CHECK (date_of_birth < CURRENT_DATE),
    CONSTRAINT user_contact_email_check CHECK (contact_email ~ '^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$'),
    CONSTRAINT user_password_check CHECK (
        length(password) >= 8 AND
        password ~ '[A-Z]' AND
        password ~ '[a-z]' AND
        password ~ '[0-9]' AND
        password ~ '[^a-zA-Z0-9]'
    )
);

CREATE TABLE "Event_Happening_Rating" (
    rating_id BIGSERIAL PRIMARY KEY,
    rating INT NOT NULL CHECK (rating BETWEEN 1 AND 10),
    comment TEXT,
    event_happening_id BIGINT NOT NULL,
    user_id BIGINT NOT NULL DEFAULT 0,

    CONSTRAINT fk_event_happening_rating_event_happening FOREIGN KEY (event_happening_id) REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT fk_event_happening_rating_user FOREIGN KEY (user_id) REFERENCES "User" (user_id)
        ON DELETE SET DEFAULT
        ON UPDATE CASCADE,
    CONSTRAINT uq_rating_happening_user UNIQUE (event_happening_id, user_id)
);


CREATE TABLE "Ticket" (
    ticket_id BIGSERIAL PRIMARY KEY,
    ticket_type VARCHAR(50) NOT NULL,
    base_price FLOAT4 NOT NULL,
    is_available BOOLEAN NOT NULL DEFAULT TRUE,
    event_happening_id BIGINT NOT NULL,
    seat_id BIGINT NOT NULL,

    CONSTRAINT fk_ticket_event_happening FOREIGN KEY (event_happening_id)
        REFERENCES "Event_Happening" (event_happening_id)
        ON DELETE RESTRICT
        ON UPDATE CASCADE,
    CONSTRAINT fk_ticket_seat FOREIGN KEY (seat_id)
        REFERENCES "Seat" (seat_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE,
    CONSTRAINT uq_ticket_event_happening_seat UNIQUE (event_happening_id, seat_id)
);

CREATE TABLE "Ticket_Purchase" (
    purchase_id BIGSERIAL PRIMARY KEY,
    ticket_id BIGINT NOT NULL,
    user_id BIGINT NOT NULL DEFAULT 0,
    qr_code VARCHAR(255) NOT NULL UNIQUE,
    purchase_time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    purchase_amount FLOAT4 NOT NULL,

    CONSTRAINT fk_purchase_ticket FOREIGN KEY (ticket_id) REFERENCES "Ticket" (ticket_id)
        ON DELETE RESTRICT
        ON UPDATE CASCADE,
    CONSTRAINT fk_purchase_user FOREIGN KEY (user_id) REFERENCES "User" (user_id)
        ON DELETE SET DEFAULT
        ON UPDATE CASCADE
);

CREATE TABLE "Ticket_Refund" (
    refund_id BIGSERIAL PRIMARY KEY,
    purchase_id BIGINT NOT NULL UNIQUE,
    refund_time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    refund_amount FLOAT4 NOT NULL,
    reason TEXT,

    CONSTRAINT fk_refund_purchase FOREIGN KEY (purchase_id) REFERENCES "Ticket_Purchase" (purchase_id)
        ON DELETE CASCADE
        ON UPDATE CASCADE
);

```

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