CREATE TABLE `AdminCostItem` (
    `id` VARCHAR(191) NOT NULL,
    `name` VARCHAR(100) NOT NULL,
    `category` VARCHAR(32) NOT NULL DEFAULT 'other',
    `amount` DOUBLE NOT NULL,
    `currency` VARCHAR(8) NOT NULL DEFAULT 'CNY',
    `purchaseDate` DATETIME(3) NOT NULL,
    `expiryDate` DATETIME(3) NULL,
    `billingCycle` VARCHAR(16) NOT NULL DEFAULT 'once',
    `note` VARCHAR(255) NULL,
    `createdAt` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
    `updatedAt` DATETIME(3) NOT NULL,
    INDEX `AdminCostItem_category_idx`(`category`),
    INDEX `AdminCostItem_expiryDate_idx`(`expiryDate`),
    PRIMARY KEY (`id`)
) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;