-- Steuerkram - Lieferantenmanagement

SET NAMES utf8mb4;

-- ============================================================
-- Lieferanten
-- ============================================================
CREATE TABLE IF NOT EXISTS suppliers (
    id          INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    name        VARCHAR(255) NOT NULL,
    created_at  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    UNIQUE KEY uq_supplier_name (name)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Lieferant-Referenz in Belege
ALTER TABLE belege
    ADD COLUMN supplier_id INT UNSIGNED NULL DEFAULT NULL AFTER belegtyp,
    ADD CONSTRAINT fk_belege_supplier
        FOREIGN KEY (supplier_id) REFERENCES suppliers (id) ON DELETE SET NULL;