CREATE TABLE password_reset_tokens (
    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    user_id BIGINT UNSIGNED NOT NULL,
    token_hash CHAR(64) NOT NULL,
    expires_at DATETIME NOT NULL,
    used_at DATETIME NULL DEFAULT NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT fk_password_reset_tokens_user FOREIGN KEY (user_id) REFERENCES users (id) ON DELETE CASCADE,
    UNIQUE KEY uq_password_reset_token_hash (token_hash),
    KEY idx_password_reset_user (user_id),
    KEY idx_password_reset_expires (expires_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;