-- Reference schema. The app auto-creates this table on first load (ensure_schema()),
-- so you normally don't need to run this manually. Kept here for reference / backups.
CREATE TABLE IF NOT EXISTS vocabulary (
    id INT AUTO_INCREMENT PRIMARY KEY,
    korean VARCHAR(255) NOT NULL,
    english VARCHAR(255) NOT NULL,
    tag VARCHAR(64) DEFAULT NULL,          -- chapter tag, e.g. "1" = chapter one
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;