-- 退款申请：iOS 用户向 Apple 申请退款后，平台发来的退款问询落库，供后台查看
CREATE TABLE `refund_requests` (
    `id` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
    `pay_order_id` VARCHAR(64) NOT NULL,
    `order_id` INTEGER UNSIGNED NULL,
    `reason` VARCHAR(255) NULL,
    `provide_status` VARCHAR(4) NULL,
    `our_result` TINYINT NOT NULL,
    `our_evidence` VARCHAR(255) NULL,
    `query_count` INTEGER UNSIGNED NOT NULL DEFAULT 1,
    `created_at` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
    `updated_at` DATETIME(3) NOT NULL,

    UNIQUE INDEX `refund_requests_pay_order_id_key`(`pay_order_id`),
    INDEX `refund_requests_created_at_idx`(`created_at`),
    PRIMARY KEY (`id`)
) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

ALTER TABLE `refund_requests` ADD CONSTRAINT `refund_requests_order_id_fkey` FOREIGN KEY (`order_id`) REFERENCES `orders`(`id`) ON DELETE SET NULL ON UPDATE CASCADE;